Polyalkylene polymer compounds and uses thereof

ABSTRACT

The invention relates to novel polyalkylene glycol compounds and methods of using them. In particular, compounds comprising a novel polyethylene glycol conjugate are used alone, or in combination with antiviral agents to treat a viral infection, such as chronic hepatitis C.

CLAIM OF PRIORITY

This application is a divisional application of U.S. patent applicationSer. No. 10/892,830, filed on Jul. 16, 2004, now U.S. Pat. No.8,017,733, which is a continuation of International Patent ApplicationSer. No. PCT/US03/01559, filed on Jan. 17, 2003, which claims thebenefit of U.S. Provisional Application Ser. No. 60/349,917, filed onJan. 18, 2002, each of which is hereby incorporated by reference in itsentirety for all purposes.

FIELD OF THE INVENTION

The invention relates to novel polyalkylene glycol compounds, conjugatesof the polymers and proteins, and uses thereof.

BACKGROUND OF THE INVENTION

Covalent attachment of hydrophilic polymers, such as polyalkylene glycolpolymers, also known as polyalkylene oxides, to biologically-activemolecules and surfaces is of interest in biotechnology and medicine.

In particular, much research has focused on the use of poly(ethyleneglycol) (PEG), also known as or poly(ethylene oxide) (PEO), conjugatesto enhance solubility and stability and to prolong the blood circulationhalf-life of molecules.

In its most common form, PEG is a linear polymer terminated at each endwith hydroxyl groups:HO—CH₂CH₂O—(CH₂CH₂O)_(n)—CH₂CH₂—OH.

The above polymer, alpha-, omega-dihydroxylpoly(ethylene glycol), canalso be represented as HO-PEG-OH, where it is understood that the-PEG-symbol represents the following structural unit:—CH₂CH₂O—(CH₂CH₂O)_(n)—CH₂CH₂—where n typically ranges from about 4 to about 10,000. PEG is commonlyused as methoxy-PEG-OH, or mPEG, in which one terminus is the relativelyinert methoxy group, while the other terminus is a hydroxyl group thatis subject to ready chemical modification. Additionally, random or blockcopolymers of different alkylene oxides (e.g., ethylene oxide andpropylene oxide) that are closely related to PEG in their chemistry canbe substituted for PEG in many of its applications.

To couple PEG to a molecule of interest, it is often necessary toactivate the PEG by preparing a derivative of the PEG having a reactivefunctional group at least at one terminus. The functional group ischosen based on the type of available reactive group on the moleculethat will be coupled to the PEG.

PEG is a polymer having the properties of solubility in water and inmany organic solvents, lack of toxicity, and lack of immunogenicity. Oneuse of PEG is to covalently attach the polymer to insoluble molecules tomake the resulting PEG-molecule “conjugate” soluble. For example, it hasbeen shown that the water-insoluble drug paclitaxel, when coupled toPEG, becomes water-soluble. Greenwald, et al., J. Org. Chem., 60:331-336(1995).

The prodrug approach, in which drugs are released by degradation of morecomplex molecules (prodrugs) under physiological conditions, is apowerful component of drug delivery. Prodrugs can, for example, beformed by bonding PEG to drugs via linkages which are degradable underphysiological conditions. The lifetime of PEG prodrugs in vivo dependsupon the type of functional group(s) forming linkages between PEG andthe drug. In general, ester linkages, formed by reaction of PEGcarboxylic acids or activated PEG carboxylic acids with alcohol groupson the drug hydrolyze under physiological conditions to release thedrug, while amide and carbamate linkages, formed from amine groups onthe drug, are stable and do not hydrolyze to release the free drug. Ithas been shown that hydrolytic delivery of drugs from PEG esters can befavorably controlled to a certain extent by controlling the number oflinking methylene groups in a spacer between the terminal PEG oxygen andthe carbonyl group of the attached carboxylic acid or carboxylic acidderivative. For example, Harris et al., in U.S. Pat. No. 5,672,662,describe PEG butanoic acid and PEG propanoic acid, and activatedderivatives thereof, as alternatives to carboxymethyl PEG for compoundswhere less hydrolytic reactivity in the corresponding ester derivativesis desirable. See, generally, PCT publication WO 01/46291.

One factor limiting the usefulness of proteinaceous substances formedical treatment applications is that, when given parenterally, theyare eliminated from the body within a short time. This elimination canoccur as a result of degradation by proteases or by clearance usingnormal pathways for protein elimination such as by filtration in thekidneys. Oral administration of these substances is even moreproblematic because, in addition to proteolysis in the stomach, the highacidity of the stomach destroys these substances before they reach theirintended target tissue. The problems associated with these routes ofadministration of proteins are well known in the pharmaceuticalindustry, and various strategies are being employed in attempts to solvethem. A great deal of work dealing with protein stabilization has beenpublished. Various ways of conjugating proteins with polymeric materialsare known, including use of dextrans, polyvinyl pyrrolidones,glycopeptides, polyethylene glycol, and polyamino acids. The resultingconjugated polypeptides are reported to retain their biologicalactivities and solubility in water for parenteral applications.

Of particular interest is increasing the biological activity ofinterferons while reducing the toxicity involved with use of theseproteins for treating human patients. Interferons are a family ofnaturally-occurring small proteins and glycoproteins produced andsecreted by most nucleated cells in response to viral infection as wellas to other antigenic stimuli. Interferons render cells resistant toviral infection and exhibit a wide variety of actions on cells. Theyexert their cellular activities by binding to specific membranereceptors on the cell surface. Once bound to the cell membrane,interferons initiate a complex sequence of intracellular events. Invitro studies have demonstrated that these include the induction ofcertain enzymes; suppression of cell proliferation, immunomodulationactivities such as enhancement of the phagocytic activity ofmacrophages; augmentation of the specific cytotoxicity of lymphocytesfor target cells; and inhibition of virus replication in virus-infectedcells.

Interferons have been tested in the treatment of a variety of clinicaldisease states. The use of human interferon beta has been established inthe treatment of multiple sclerosis. Two forms of recombinant interferonbeta, have recently been licensed in Europe and the U.S. for treatmentof this disease: interferon-beta-1a (AVONEX®, Biogen, Inc., Cambridge,Mass. and REBIF® Serono, Geneva, Switzerland) and interferon-beta-1b(BETASERON®, Berlex, Richmond, Calif.). Interferon beta-1a is producedin mammalian cells using the natural human gene sequence and isglycosylated, whereas interferon beta-1b is produced in E. coli bacteriausing a modified human gene sequence that contains a geneticallyengineered cysteine-to-serine substitution at amino acid position 17 andis non-glycosylated.

Non-immune interferons, which include both alpha and beta interferons,are known to suppress human immunodeficiency virus (HIV) in both acutelyand chronically-infected cells. See Poli and Fauci, 1992, AIDS Researchand Human Retroviruses 8(2):191-197. Due to their antiviral activity,interferons, in particular alpha interferons, have received considerableattention as therapeutic agents in the treatment of hepatitis C virus(HCV)-related disease. See Hoofnagle et al., in: Viral Hepatitis 1981International Symposium, 1982, Philadelphia, Franklin Institute Press;Hoofnagle et al., 1986, New Eng. J. Med. 315:1575-1578; Thomson, 1987,Lancet 1:539-541 Kiyosawa et al., 1983, in: Zuckerman, ed., ViralHepatitis and Liver Disease, Allen K. Liss, New York pp. 895-897;Hoofnagle et al., 1985, Sem. Liv. Dis., 1985, 9:259-263.

Interferon-polymer conjugates are described in, for example, U.S. Pat.No. 4,766,106, U.S. Pat. No. 4,917,888, European Patent Application No.0 236 987, European Patent Application No. 0 510 356 and InternationalApplication Publication No. WO 95/13090.

Chronic hepatitis C is an insidious and slowly progressive diseasehaving a significant impact on the quality of life. Despite improvementin the quality of the blood-donor pool and the recent implementation oftesting of donated blood for HCV, the estimated incidence of acuteinfection among persons receiving transfusions is 5 to 10%. See Alter etal., in: Zuckerman, ed., Viral Hepatitis and Liver Disease, Allen K.Liss, New York. 1988, pp. 537-542. Thus, of the approximately 3 millionpersons who receive transfusions in the United States each year, acutehepatitis C will develop in about 150,000. While many patients whocontract hepatitis C will have subclinical or mild disease,approximately 50% will progress to a chronic disease state characterizedby fluctuating serum transaminase abnormalities and inflammatory lesionson liver biopsy. It is estimated that cirrhosis will develop in up toabout 20% of this group. See Koretz et al., 1985, Gastroenterology88:1251-1254.

Interferons are known to affect a variety of cellular functions,including DNA replication, and RNA and protein synthesis, in both normaland abnormal cells. Thus, cytotoxic effects of interferon are notrestricted to tumor or virus-infected cells but are also manifested innormal, healthy cells. As a result, undesirable side effects may ariseduring interferon therapy, particularly when high doses are required.Administration of interferon can lead to myelosuppression, therebyresulting in reduced red blood cell count, and reduced white blood celland platelet levels. Interferons commonly give rise to flu-like symptoms(e.g., fever, fatigue, headaches and chills), gastrointestinal disorders(e.g., anorexia, nausea and diarrhea), dizziness and coughing. Often,the sustained response of HCV patients to non-PEGylated interferontreatment is low and the treatment can induce severe side effects,including, but not limited to, retinopathy, thyroiditis, acutepancreatitis, and depression.

The undesirable side effects that accompany interferon therapyfrequently limit the therapeutic usefulness of interferon treatmentregimes. Thus, a need exists to maintain or improve the therapeuticbenefits of such therapy while reducing or eliminating the undesirableside effects.

SUMMARY OF THE INVENTION

The invention relates to novel polyalkylene glycol compounds, conjugatesof these compounds, and uses thereof.

In one aspect, the invention relates to an activated polyalkylene glycolpolymer having the structure according to Formula I:

wherein P is a polyalkylene glycol polymer;

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′;

Q is a C₃ to C₃ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, sulfamoyl, sulfonate,silyl, ether, and alkylthio;

each R′, Z and Z′ is independently hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,sulfamoyl, sulfonate, silyl, ether, and alkylthio;

R is a moiety suitable for forming a bond between the compound ofFormula I and a biologically-active compound or precursor thereof;

m is 0 or 1;

each n is independently 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In another aspect, the invention relates to an activated polyalkyleneglycol compound (PGC) having the structure according to Formula Ia:

where P is a polyalkylene glycol polymer, m is zero or one, n is zero oran integer from one to five, and X and Y are independently O, S, CO,CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. If present, thesubstituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,sulfamoyl, sulfonate, silyl, ether, or alkylthio. Heterocyclic andcarbocyclic groups include fused bicyclic and bridged bicyclic ringstructures.

Each R′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group. The substituents can behalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

Compounds which include chiral carbons can be in the R configuration,the S configuration, or may be racemic.

R is a moiety suitable for forming a bond between the compound ofFormula I and a biologically-active compound or precursor thereof.

In one embodiment, R is a carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or a glyoxal moiety.

In certain embodiments, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a),  Formula IIwhere E is hydrogen or a straight- or branched-chain C₁ to C₂₀ alkylgroup and a is an integer from 4 to 10,000. For example, E can be amethyl group.

In other embodiments, E can be a detectable label, such as, for example,a radioactive isotope, a fluorescent moiety, a phosphorescent moiety, achemiluminescent moiety, or a quantum dot.

In yet other embodiments, E is a moiety suitable for forming a bondbetween the compound of Formula I and a biologically-active compound orprecursor thereof. For example, E can be a carboxylic acid, ester,aldehyde, aldehyde hydrate, acetal, hydroxy, protected hydroxy,carbonate, alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,or a glyoxal moiety.

In still other embodiments, E has the structure according to Formula IIIor Formula IV:

where each Q, X, Y, Z, m, and n are, independently, as defined above;and each W is, independently, hydrogen or a C₁ to C₇ alkyl.

R″ is a moiety suitable for forming a bond between the compound ofFormula III and a biologically-active compound or precursor thereof, andR′″ is a moiety suitable for forming a bond between the compound ofFormula IV and a biologically-active compound or precursor thereof. Forexample, R″ and R′″ can be a carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or a glyoxal moiety.R″ and R′″ can be the same or different from R.

In particular embodiments, Q is a substituted or unsubstituted alkaryl.

In another aspect, the invention relates to an activated PGC having thestructure according to Formula V:

where P, X, Y, R′, Z, R, m, and n are as defined, and T₁ and T₂ are,independently, absent, or a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, a C₃ to C₈ saturatedor unsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group, or a substituted orunsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group. The substituents can behalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

L may be absent (e.g., d is zero) or there may be from one to four(e.g., n is an integer from one to four) L substituents on the aromaticring in addition to the T₁ and T₂ substituents, and each L is,independently, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup. The substituents are selected from halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio.

R is a moiety suitable for forming a bond between the compound ofFormula V and a biologically-active compound or precursor thereof. Forexample, R is chosen from carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal.

In one embodiment of the activated polyalkylene glycol polymer ofFormula V, P is a polyethylene glycol having the structure of FormulaII:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is hydrogen or a straight- or branched-chain C₁ to C₂₀ alkylgroup and a is an integer from 4 to 10,000. For example, E can bemethyl. In other embodiments, E is a detectable label, such as, forexample, a radioactive isotope, fluorescent moiety, phosphorescentmoiety, chemiluminescent moiety, or a quantum dot.

In another aspect, P is a polyethylene glycol having the structure ofFormula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is a moiety suitable for forming a bond between the compound ofFormula V and a biologically-active compound or precursor thereof and ais an integer from 4 to 10,000. For example, E is chosen from carboxylicacid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy, protectedhydroxy, carbonate, alkenyl, acrylate, methacrylate, acrylamide,substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

In another aspect, E has the structure according to Formula III orFormula IV:

where Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl; the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, and thesubstituents can be of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

X, Y, Z, m, and n are as defined, and each W is, independently, hydrogenor a C₁ to C₇ alkyl; and R″ is a moiety suitable for forming a bondbetween the compound of Formula III and a biologically-active compoundor precursor thereof, and R′″ is a moiety suitable for forming a bondbetween the compound of Formula IV and a biologically-active compound orprecursor thereof.

In certain embodiments, R″ and R′″ can be the same as or different fromR, and are chosen from carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal moieties.In one embodiment of the compound of Formula V, X and Y, if present, areoxygen.

In another aspect the invention relates to an activated PGC having thestructure according to Formula VI:

where P is a polyalkylene glycol polymer, m is zero or one, n is zero oran integer from one to five, X and Y are independently O, S, CO, CO₂,COS, SO, SO₂, CONR′, SO₂NR′, or NR′, and T₁ and T₂ are, independently,absent, or a straight- or branched-chain, saturated or unsaturated C₁ toC₂₀ alkyl or heteroalkyl group.

Each R′ and Z is, independently, hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup.

d is zero or an integer from one to four, and each L is, independently,a straight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkylor heteroalkyl group, C₃ to C₈ saturated or unsaturated cyclic alkyl orcyclic heteroalkyl, a substituted or unsubstituted aryl or heteroarylgroup or a substituted or unsubstituted alkaryl wherein the alkyl is aC₁ to C₂₀ saturated or unsaturated alkyl or heteroalkaryl group. Thesubstituents are selected from halogen, hydroxyl, carbonyl, carboxylate,ester, formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio moieties.

In one embodiment, the activated PGC according to Formula VI has thestructure according to Formula VII or Formula VIII:

In one embodiment of the activated polyalkylene glycol compounds ofFormulae VII and VIII, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is hydrogen or a straight- or branched-chain C₁ to C₂₀ alkylgroup and a is an integer from 4 to 10,000. For example, E can bemethyl. In other embodiments, E is a detectable label, such as, forexample, a radioactive isotope, fluorescent moiety, phosphorescentmoiety, chemiluminescent moiety, or a quantum dot.

In another aspect, P is a polyethylene glycol having the structure ofFormula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is a moiety suitable for forming a bond between the compound ofFormula VII or VIII and a biologically-active compound or precursorthereof and a is an integer from 4 to 10,000. For example, E is chosenfrom carboxylic acid, ester, aldehyde, aldehyde hydrate, acetal,hydroxy, protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

In another aspect, E has the structure according to Formula III orFormula N:

where Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl; the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, and thesubstituents can be of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio. Heterocyclicand carbocyclic groups include fused bicyclic and bridged bicyclic ringstructures X, Y, Z, m, and n are as defined, and each W is,independently, hydrogen or a C₁ to C₇ alkyl; and R″ is a moiety suitablefor forming a bond between the compound of Formula III and abiologically-active compound or precursor thereof, and R′″ is a moietysuitable for forming a bond between the compound of Formula IV and abiologically-active compound or precursor thereof.

In certain embodiments, R″ and R′″ can be the same as or different fromR, and are chosen from carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal moieties.

In one embodiment, the activated polyalkylene glycol compound of FormulaVIII, the ring substituents are located in a meta arrangement. Inanother embodiment, the ring substituents are located in a paraarrangement.

In another embodiment, the activated polyalkylene glycol compoundaccording to Formula VI, has the structure according to Formula IX:

where P is a polyalkylene glycol polymer, each n and u are,independently, zero or an integer from one to five; and Z is hydrogen, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group.

In one embodiment of the compounds of Formula IX, the ring substituentsare located in a meta arrangement. In another embodiment of thecompounds of Formula IX, the ring substituents are located in a paraarrangement.

In another embodiment of the compounds of Formula IX, P is apolyethylene glycol having the structure of Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, a detectable label, or a moiety suitable for forming a bondbetween the compound of Formula IX and a biologically-active compound orprecursor thereof and a is an integer from 4 to 10,000.

In another aspect, the invention involves an activated polyalkyleneglycol polymer having the structure according to Formula X:

wherein P is a polyalkylene glycol polymer;

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′;

R′ is hydrogen, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

Z and Z′ are individually hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio, provided that at least one Z or Z′ is not hydrogen;

R is a moiety suitable for forming a bond between the compound ofFormula X and a biologically-active compound or precursor thereof;

each n is independently 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In another aspect, the invention involves an activated polyalkyleneglycol compound (PGC) having the structure according to Formula Xa:

In these compounds, P is a polyalkylene glycol polymer, such as, forexample, PEG or mPEG.

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′, and R′, ifpresent, is hydrogen, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

Z is a straight- or branched-chain, saturated or unsaturated C₁ to C₂₀alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturated cyclicalkyl or cyclic heteroalkyl, a substituted or unsubstituted aryl orheteroaryl group or a substituted or unsubstituted alkaryl wherein thealkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

R is a moiety suitable for forming a bond between the compound ofFormula X and a biologically-active compound or precursor thereof; and

n is 0 or an integer from 1 to 5, such that there are between zero andfive methylene groups between X and the Z-containing carbon.

In one embodiment, R is chosen from the group consisting of carboxylicacid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy, protectedhydroxy, carbonate, alkenyl, acrylate, methacrylate, acrylamide,substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In another embodiment, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; and a is an integer from 4 to 10,000. In afurther embodiment, E may be methyl.

In yet another embodiment, P is a polyethylene glycol having thestructure of Formula II, wherein E is a moiety suitable for forming abond between the compound of Formula X and a biologically-activecompound or precursor thereof and a is an integer from 4 to 10,000.

In an additional embodiment, E is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal. Alternatively, E may have the structure according toFormula III:

wherein P is a polyalkylene glycol polymer,

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′;

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

R′ and each Z are independently as described above;

m is 0 or 1;

each W is, independently, hydrogen or a C₁ to C₇ alkyl;

each n is independently 0 or an integer from 1 to 5; and

R″ is a moiety suitable for forming a bond between the compound ofFormula III and a biologically-active compound or precursor thereof.Heterocyclic and carbocyclic groups include fused bicyclic and bridgedbicyclic ring structures.

In still a further embodiment, E has the structure according to FormulaIV:

wherein each X, Z and n are, independently, as defined;

each W is, independently, hydrogen or a C₁ to C₇ alkyl; and

R′″ is a moiety suitable for forming a bond between the compound ofFormula IV and a biologically-active compound or precursor thereof.

In an additional embodiment, R″ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In a further embodiment, R′ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In another embodiment, E is a detectable label. Additionally, E may beselected from the group consisting of radioactive isotopes, fluorescentmoieties, phosphorescent moieties, chemiluminescent moieties, andquantum dots.

In still another embodiment, the activated PGC according to theinvention has the structure according to Formula XI:

wherein P is a polyalkylene glycol polymer; and

n and Z are as defined.

In another embodiment, the activated polyalkylene glycol has thestructure according to Formula XII:

wherein n, a, and Z are as defined above. In one embodiment, Z may bemethyl. In some embodiments, n is one.

In another aspect, the invention involves an activated polyalkyleneglycol compound of having the structure according to Formula XIII:

where a is an integer from 4 to 10,000.

The invention is also concerned with a composition of the activatedpolyalkylene glycol compounds of the invention and a biologically-activecompound or precursor thereof. In various embodiments, thebiologically-active compound or precursor thereof is chosen from thegroup consisting of a peptide, peptide analog, protein, enzyme, smallmolecule, dye, lipid, nucleoside, oligonucleotide, oligonucleotideanalog, sugar, oligosaccharide, cell, virus, liposome, microparticle,surface, and a micelle.

In another aspect, the invention provides a composition having thestructure according to Formula XIV:

wherein P is a polyalkylene glycol polymer,

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′;

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each R′, Z, and Z′ is independently hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, C₃ to C₉ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

R* is a linking moiety;

B is a biologically-active compound or precursor thereof;

m is 0 or 1;

each n is independently 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In another aspect, the invention involves a composition having thestructure according to Formula XIVa:

wherein P is a polyalkylene glycol polymer;

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′;

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group(including fused bicyclic and bridged bicyclic ring structures), or asubstituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each R′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio;

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof;

B is a biologically-active compound or precursor thereof afterconjugation with R;

m is 0 or 1; and

n is 0 or an integer from 1 to 5.

In one embodiment, R* is a linking moiety formed from the reaction of Rwith a biologically-active compound or precursor thereof. For example, Ris a moiety selected from the group consisting of carboxylic acid,ester, aldehyde, aldehyde hydrate, acetal, hydroxy, protected hydroxy,carbonate, alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In another embodiment, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; and a is an integer from 4 to 10,000. Inthis embodiment, E may be methyl.

In a further embodiment, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwherein E is a moiety suitable for forming a bond between the compoundof Formula XIV and a biologically-active compound or precursor thereofand a is an integer from 4 to 10,000. Here, in still a furtherembodiment, E may form a bond to another biologically-active compound,B. Alternatively, E may form a bond to a biologically-active compoundother than B. E may also form an additional bond to thebiologically-active compound, B.

In various embodiments, E may be chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal. In another embodiment, E may have the structure accordingto Formula III:

wherein each Q, X, Y, Z, m, and n are, independently, as defined, each Wis, independently, hydrogen or a C₁ to C₇ alkyl; and R″ is a moietysuitable for forming a bond between the compound of Formula III and abiologically-active compound or precursor thereof.

In a further embodiment, E has the structure according to Formula IV:

wherein each X, Z and n are, independently, as defined, each W is,independently, hydrogen or a C₁ to C₇ alkyl; and

R′″ is a moiety suitable for forming a bond between the compound ofFormula IV and a biologically-active compound or precursor thereof.

In various embodiments, R″ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

Likewise, in other embodiments, R′″ is chosen from the group consistingof carboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In still other embodiments, E is a detectable label. For example, E maybe selected from the group consisting of radioactive isotopes,fluorescent moieties, phosphorescent moieties, chemiluminescentmoieties, and quantum dots.

In various embodiments, Q is a substituted or unsubstituted alkaryl.

In another aspect, the invention involves a composition having thestructure according to Formula XV:

wherein P is a polyalkylene glycol polymer, m is zero or one; d is zeroor an integer from one to four, and n is zero or an integer from one tofive.

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′; and T₁ and T₂ are, independently, absent, or a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀alkyl or heteroalkylgroup, a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

Each R′ and Z is, independently, hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

Each L is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

For example, R may be a moiety selected from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In another embodiment, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

wherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; and a is an integer from 4 to 10,000. Inthis embodiment, E may be methyl.

In still another aspect, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

wherein E is a moiety suitable for forming a bond between the compoundof Formula XV and a biologically-active compound or precursor thereofand a is an integer from 4 to 10,000. Here, E may be selected from thegroup consisting of carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal.Additionally, E may have the structure according to:

wherein Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each X, Y, Z, m, and n are, independently, as defined;

each W is, independently, hydrogen or a C₁ to C₇ alkyl; and

R″ is a moiety suitable for forming a bond between the compound ofFormula III and a biologically-active compound or precursor thereof.

In another embodiment, E can have the structure according to Formula IV:

wherein X, Z and n are as defined;

each W is, independently, hydrogen or a C₁ to C₇ alkyl; and

R′″ is a moiety suitable for forming a bond between the compound ofFormula IV and a biologically-active compound or precursor thereof.

In still another embodiment, R″ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

Likewise, in other embodiments, R′″ may selected from the groupconsisting of carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal.

In other embodiments, E is a detectable label. For example, E may beselected from the group consisting of radioactive isotopes, fluorescentmoieties, phosphorescent moieties, chemiluminescent moieties, andquantum dots.

In another aspect, the invention relates to a composition having thestructure according to Formula XVI:

where m is 0 or 1, n is 0 or an integer from Ito 5, P is a polyalkyleneglycol polymer, X and Y are independently O, S, CO, CO₂, COS, SO, SO₂,CONR′, SO₂NR′, or NR′, T₁ and T₂ are, independently, absent, or astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group, and each R′ and Z is independently hydrogen, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group;

d is 0 or an integer from 1 to 4, and each L is, independently, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group, C₃ to C₈ saturated or unsaturated cyclic alkyl orcyclic heteroalkyl, a substituted or unsubstituted aryl or heteroarylgroup or a substituted or unsubstituted alkaryl wherein the alkyl is aC₁ to C₂₀ saturated or unsaturated alkyl or heteroalkaryl group. Thesubstituents are selected from halogen, hydroxyl, carbonyl, carboxylate,ester, formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio groups.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

For example, R may be a moiety selected from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In one embodiment, R* is a methylene group and B is abiologically-active molecule having an amino group, where the methylenegroup forms a bond with the amino group on B.

In certain embodiments, the amine is the amino terminus of a peptide, anamine of an amino acid side chain of a peptide, or an amine of aglycosylation substituent of a glycosylated peptide. For example, thepeptide can be an interferon, such as interferon-beta, e.g.,interferon-beta-1a.

In some embodiments, the compound according to Formula XVI has astructure according to Formula XVII:

where P is a polyalkylene glycol polymer, Z is hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, n is 0 or an integer from 1 to 5.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and 13 is abiologically-active compound, or precursor thereof, after conjugationwith R.

For example, R may be a moiety selected from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In one embodiment, R* of Formula XVII is a methylene group and B is abiologically-active molecule having an amino group, where the methylenegroup forms a bond with the amino group on B.

In certain embodiments, the amine is the amino terminus of a peptide, anamine of an amino acid side chain of a peptide, or an amine of aglycosylation substituent of a glycosylated peptide. For example, thepeptide can be an interferon, such as interferon-beta, e.g.,interferon-beta-1a.

In other embodiments, the compound according to Formula XVI has astructure according to Formula XVIII:

where P is a polyalkylene glycol polymer, R* is a linking moiety, B is abiologically-active molecule, and n is one or two.

In one embodiment, R* of Formula XVIII is a methylene group and B is abiologically-active molecule having an amino group, where the methylenegroup forms a bond with the amino group on B.

In certain embodiments, the amine is the amino terminus of a peptide, anamine of an amino acid side chain of a peptide, or an amine of aglycosylation substituent of a glycosylated peptide. For example, thepeptide can be an interferon, such as interferon-beta, e.g.,interferon-beta-1a.

In certain embodiments of the compound according to Formula XVI, P is apolyethylene glycol having the structure of Formula H:E-(O—CH₂CH₂)_(a)—,  Formula II

wherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkyl(e.g., methyl) group, a detectable label, or a moiety suitable forforming a bond between the compound of Formula XVI and abiologically-active compound or precursor thereof and a is an integerfrom 4 to 10,000. When E is a detectable label, the label can be, forexample, a radioactive isotope, fluorescent moiety, phosphorescentmoiety, chemiluminescent moiety, or a quantum dot.

In another embodiment, where E is a moiety suitable for forming a bondbetween the compound of Formula XVI and a biologically-active compoundor precursor thereof, E is chosen from carboxylic acid, ester, aldehyde,aldehyde hydrate, acetal, hydroxy, protected hydroxy, carbonate,alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

In another embodiment, E has the structure according to Formula III orFormula IV:

where Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl; the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, and thesubstituents can be of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

X, Y, Z, m, and n are as defined, and each W is, independently, hydrogenor a C₁ to C₇ alkyl; and R″ is a moiety suitable for forming a bondbetween the compound of Formula III and a biologically-active compoundor precursor thereof, and R′″ is a moiety suitable for forming a bondbetween the compound of Formula IV and a biologically-active compound orprecursor thereof.

In certain embodiments, R″ and R′″ can be the same as or different fromR, and are chosen from carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal moieties.

In other embodiments of the compound according to Formula XVI, thecompound can have the structure according to Formula XIX:

wherein P is a polyalkylene glycol polymer, each n and u are,independently, zero or an integer from one to five, Z is hydrogen, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In one embodiment, V of Formula XIX is a methylene group and B is abiologically-active molecule having an amino group, where the methylenegroup forms a bond with the amino group on B.

In certain embodiments, the amine is the amino terminus of a peptide, anamine of an amino acid side chain of a peptide, or an amine of aglycosylation substituent of a glycosylated peptide. For example, thepeptide can be an interferon, such as interferon-beta, e.g.,interferon-beta-1a.

In another aspect, the invention relates to a composition according toFormula XX:

where m is 0 or 1, d is 0 or an integer from 1 to 4, a is an integerfrom 4 to 10,000, and n is 0 or an integer from 1 to 5.

Each X and Y is independently O, S, CO, CO₂, COS, SO, SO₂, CONR′,SO₂NR′, or NR′, or NR′, T₁ and T₂ are, independently, absent, or astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group, and each R′ and Z is independently hydrogen, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group.

When present, each L is, independently, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group. The substituents are selectedfrom halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. The substituentscan be halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

Each W is, independently, hydrogen or a C₁ to C₇ alkyl.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In another aspect, the invention relates to a composition according toFormula XXI:

where m is 0 or 1, d is 0 or an integer from 1 to 4, a is an integerfrom 4 to 10,000, and n is 0 or an integer from 1 to 5.

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′, T₁ and T₂ are, independently, absent, or a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, each R′ and Z is, independently, hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup.

When present, each L is, independently, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from halogen, hydroxyl, carbonyl, carboxylate, ester, formyl,acyl, thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl,phosphoryl, phosphonate, phosphinate, amino, amido, amidine, imine,cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio, and each Wis, independently, hydrogen or a C₁ to C₇ allyl.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In another aspect, the invention involves a composition having thestructure according to Formula XXII:

wherein P is a polyalkylene glycol polymer,

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′;

R′ is hydrogen, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a Substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each Z and Z′ is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio, provided that at least one Z or Z′ is not hydrogen;

R* is a linking moiety;

B is a biologically-active molecule;

each n is 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In a further aspect, the invention involves a composition having thestructure according to Formula XXIIa:

wherein P is a polyalkylene glycol polymer;

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; and n is 0 oran integer from 1 to 5.

R′ is hydrogen, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

Z is a straight- or branched-chain, saturated or unsaturated C₁ to C₂₀alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturated cyclicalkyl or cyclic heteroalkyl, a substituted or unsubstituted aryl orheteroaryl group or a substituted or unsubstituted alkaryl wherein thealkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In one embodiment, R* is formed from the reaction of a moiety selectedfrom the group consisting of carboxylic acid, ester, aldehyde, aldehydehydrate, acetal, hydroxy, protected hydroxy, carbonate, alkenyl,acrylate, methacrylate, acrylamide, substituted or unsubstituted thiol,halogen, substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, and glyoxal with abiologically-active compound or precursor thereof.

In an additional embodiment, P is a polyethylene glycol having thestructure of Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

wherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; and a is an integer from 4 to 10,000. Inthis embodiment, E may be methyl.

In another embodiment, P is a polyethylene glycol having the structureof Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

wherein E is a moiety suitable for forming a bond between the compoundof Formula II and a biologically-active compound or precursor thereofand a is an integer from 4 to 10,000. In this embodiment, E may bind toa biologically-active compound or precursor thereof other than B. Inother embodiments, E forms an additional bond to the biologically-activecompound B.

In various embodiments, E may be selected from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In other embodiments, E has the structure according to Formula III:

wherein P is a polyalkylene glycol polymer,

each X and Y is independently O, S, CO, CO₂, COS, SO, SO₂, CONR′,SO₂NR′, or NR′;

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

R′ and each Z are independently as described above;

m is 0 or 1;

each n is independently 0 or an integer from 1 to 5;

R″ is a moiety suitable for forming a bond between the compound ofFormula III and a biologically-active compound or precursor thereof; and

each W is, independently, hydrogen or a C₁ to C₇ alkyl.

In a further embodiment, E has the structure according to Formula IV:

wherein each X, Z and n are, independently, as defined;

each W is, independently, hydrogen or a C₁ to C₇ alkyl; and

R′″ is a moiety suitable for forming a bond between the compound ofFormula IV and a biologically-active compound or precursor thereof.

In still further embodiments, R″ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In yet other embodiments, R′″ is chosen from the group consisting ofcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal.

In additional embodiments, E is a detectable label. For example, E maybe selected from the group consisting of radioactive isotopes,fluorescent moieties, phosphorescent moieties, chemiluminescent moietiesand quantum dots.

In another embodiment, R* is methylene and B is a biologically-activemolecule attached via an amine. For example, the amine is the aminoterminus of a peptide. In a further embodiment, the peptide is aninterferon such as interferon-beta-1a.

In another embodiment, the invention is a composition having thestructure according to Formula XXIII:

wherein n, a, R* B, and Z are as defined above. In one additionalembodiment, Z is methyl and n is one.

In still a further aspect, the invention involves a compositionaccording to Formula XXIV:

wherein m is 0 or 1, a is an integer from 4 to 10,000; and each n isindependently zero or an integer from 1 to 5. Each X and Y isindependently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; eachR′ and Z is, independently, hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group; and eachW is, independently, hydrogen or a C₁ to C₇ alkyl.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In a further aspect, the invention involves a composition according toFormula XXV:

wherein

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; a is an integerfrom 4 to 10,000; and each n is independently 0 or an integer from 1 to5.

Each and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, and eachW is, independently, hydrogen or a C₁ to C₇ alkyl.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

The invention also involves a pharmaceutical composition containing thecompositions of the invention along with a pharmaceutically-acceptablecarrier. In various embodiments, the pharmaceutical composition alsocontains an additional biologically-active agent. For example, thebiologically-active agent may be selected from the group consisting of apeptide, peptide analog, protein, enzyme, small molecule, dye, lipid,nucleoside, oligonucleotide, oligonucleotide analog, sugar,oligosaccharide, cell, virus, liposome, microparticle, surface, and amicelle. In another embodiment, the biologically-active agent is anantiviral agent.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula I and abiologically-active compound or a precursor thereof (B).

In one embodiment, the composition has the structure according toFormula XIV:

where all variables are as defined above, and R* is a linking moietyformed by the reaction of R with a reactive moiety on thebiologically-active compound or precursor thereof; and B is abiologically-active compound or precursor thereof.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula V and abiologically-active compound or a precursor thereof. In one embodiment,the composition has the structure according to Formula XV:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In yet another embodiment, the composition has the structure accordingto Formula XX or XXI:

where all variables are as defined above, each W is, independently,hydrogen or a C₁ to C₇ alkyl, R* is a linking moiety formed by thereaction of R with a reactive moiety on the biologically-activecompound, B, or precursor thereof; R** is a linking moiety formed by thereaction of R″ or R′″ with a reactive moiety on the biologically-activecompound, B′, or precursor thereof; and B and B′ are, independently, abiologically-active compound or precursor thereof. In some embodiments,B and B′ are the same type of biologically-active compound. In otherembodiments, B and B′ are different biologically-active compounds. Instill other embodiments, B and B′ are the same biologically activemolecule. In additional embodiments, R* and R** are the same. In otherembodiments, R* and R** are different.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound Formula VI and abiologically-active compound or a precursor thereof.

In one embodiment; the composition has the structure according toFormula XVI:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula VII and abiologically-active compound or a precursor thereof.

In one embodiment, the composition has the structure according toFormula XVII:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula VIII and abiologically-active compound or a precursor thereof.

In one embodiment, the composition has the structure according toFormula XVIII:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula IX and abiologically-active compound or a precursor thereof.

In one embodiment, the composition has the structure according toFormula XIX:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In another aspect, the invention relates to a composition comprising theproduct of the reaction of the compound of Formula X and abiologically-active compound or a precursor thereof.

In one embodiment, the composition has the structure according toFormula XXII:

where all variables are as defined above, R* is a linking moiety formedby the reaction of R with a reactive moiety on the biologically-activecompound or precursor thereof; and B is a biologically-active compoundor precursor thereof.

In another embodiment, the composition has the structure the structureaccording to Formula XXIV:

where all variables are as defined above, each W is, independently,hydrogen or a C₁ to C₇ alkyl. R* is a linking moiety formed by thereaction of R with a reactive moiety on the biologically-activecompound, B, or precursor thereof, R** is a linking moiety formed by thereaction of R″ with a reactive moiety on the biologically-activecompound, B′, or precursor thereof; and B and B′ are, independently, abiologically-active compound or precursor thereof. In some embodiments,B and B′ are the same type of biologically-active compound. In otherembodiments, B and B′ are different biologically-active compounds. Instill other embodiments, B and B′ are the same biologically activemolecule. In additional embodiments, R* and R** are the same. In otherembodiments, R* and R** are different.

In other embodiments, the composition has the structure according toFormula XXV:

where all variables are as defined in claims above, each W is,independently, hydrogen or a C₁ to C₇ alkyl.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In another aspect, the invention involves a method of treating a patientwith a susceptible viral infection, comprising administering to thepatient an effective amount of a composition having the structureaccording to Formula XIV:

wherein P is a polyalkylene glycol polymer,

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′;

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each R′, Z and Z′ is independently hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

R* is a linking moiety;

B is a biologically-active compound or precursor thereof;

m is 0 or 1;

each n is 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In a further aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XIVa:

wherein P is a polyalkylene glycol polymer, m is 0 or 1; and n is 0 oran integer from 1 to 5.

X and Y are independently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′; and Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

Each R′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio;

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In one embodiment, B is a biologically-active peptide such asinterferon. For example, this interferon may be interferon-beta-1a.

In further embodiments, the composition also includes abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In various embodiments, the viral infection in need of treatment ischronic hepatitis C.

In an additional aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XV:

wherein P is a polyalkylene glycol polymer, m is 0 or 1; d is 0 or aninteger from 1 to 4; n is 0 or an integer from 1 to 5; and X and Y areindependently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′.

T₁ and T₂ are, independently, absent, or a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, a C₃ toC₈ saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group, or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio.

Each R′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio.

Each L is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio;

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, in one embodiment, B is interferon-beta-1a.

In another embodiment, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.In other embodiments, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803. Inaddition, the viral infection can be chronic hepatitis C.

In a further aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XVI:

where P is a polyalkylene glycol polymer, m is 0 or 1; d is 0 or aninteger from 1 to 4; n is 0 or an integer from 1 to 5; X and Y areindependently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; T₁ andT₂ are, independently, absent, or a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group; and eachR′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group.

Each L is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, B may be interferon-beta-1a.

In still further embodiments, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudineacyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In another embodiment, the viral infection is chronic hepatitis C.

In a further aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XX:

wherein m is 0 or 1; d is 0 or an integer from 1 to 4; a is an integerfrom 4 to 10,000; and n is 0 or an integer from 1 to 5.

Each X and Y is independently O, S, CO, CO₂, COS, SO, SO₂, CONR′,SO₂NR′, or NR′; T₁ and T₂ are, independently, absent, or a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup; each R′ and Z is independently hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup; and each W is, independently, hydrogen or a C₁ to C₇ alkyl.

Each L is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, in one embodiment, B is interferon-beta-1a.

In other embodiments, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In a further embodiment, the viral infection is chronic hepatitis C.

In a further aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XXI:

where m is 0 or 1; d is 0 or an integer from 1 to 4; a is an integerfrom 4 to 10,000; each n is 0 or an integer from 1 to 5; each X and Y isindependently O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; T₁ andT₂ are, independently, absent, or a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group; each R′and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group; and eachW is, independently, hydrogen or a C₁ to C₇ alkyl.

Each L is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In various embodiments, B is a biologically-active peptide such as aninterferon. For example, B may be is interferon-beta-1a.

In another embodiment, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In a further embodiment, the viral infection is chronic hepatitis C.

In another aspect, the invention involves a method of treating a patientwith a susceptible viral infection, comprising administering to thepatient an effective amount of a composition having the structureaccording to Formula XXII:

wherein

P is a polyalkylene glycol polymer,

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′;

R′ is hydrogen, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio;

each Z and Z′ is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio provided that at least one Z or Z′ is not hydrogen;

R* is a linking moiety;

B is a biologically-active molecule.

m is 0 or 1;

each n is 0 or an integer from 1 to 5; and

p is 1, 2, or 3.

In still another aspect, the invention involves a method of treating apatient with a susceptible viral infection, comprising administering tothe patient an effective amount of a composition having the structureaccording to Formula XXIIa:

where: P is a polyalkylene glycol polymer, m is 0 or 1; n is 0 or aninteger from 1 to 5; X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, orNR′; and R′ is hydrogen, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group, wherein the substituents are selected from thegroup consisting of halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, and alkylthio.

Z is a straight- or branched-chain, saturated or unsaturated C₁ to C₂₀alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturated cyclicalkyl or cyclic heteroalkyl, a substituted or unsubstituted aryl orheteroaryl group or a substituted or unsubstituted alkaryl wherein thealkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup, wherein the substituents are selected from the group consistingof halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

R* is a linking moiety formed from the reaction of R with abiologically-active compound or precursor thereof, and B is abiologically-active compound, or precursor thereof, after conjugationwith R.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, B may be interferon-beta-1a.

In another embodiment, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In a further embodiment, the viral infection is chronic hepatitis C.

In yet another aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XXIV:

where: m is 0 or 1; a is an integer from 4 to 10,000; each n isindependently 0 or an integer from 1 to 5; each X and Y is independentlyO, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; each R′ and Z isindependently hydrogen, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group; and each W is,independently, hydrogen or a C₁ to C₇ alkyl.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group, wherein thesubstituents are selected from the group consisting of halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, and alkylthio.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R.*and R** are the same. In other embodiments, R* and R** are different.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, B may be interferon-beta-1a.

In other embodiments, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In still other embodiments, the viral infection is chronic hepatitis C.

In an additional aspect, the invention involves a method of treating apatient with a susceptible viral infection by administering to thepatient an effective amount of a composition having the structureaccording to Formula XXV:

wherein each W is, independently, hydrogen or a C₁ to C₇ alkyl; a is aninteger from 4 to 10,000; each n is independently 0 or an integer from 1to 5; X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′; and eachand Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀alkyl or heteroalkyl group.

R* and R** are, independently, linking moieties formed from the reactionof R and R″ with a biologically-active compound or precursor thereof,and B and B′ are each a biologically-active compound, or precursorthereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different.

In various embodiments, B is a biologically-active peptide such asinterferon. For example, B may be interferon-beta-1a.

In another embodiment, the composition further contains abiologically-active agent selected from the group consisting of a smallmolecule antiviral, a nucleic acid antiviral and a peptidic antiviral.For example, the antiviral agent may be selected from the groupconsisting of ribavirin, levovirin, 3TC, FTC, MB686, zidovudine,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

In still other embodiments, the viral infection is chronic hepatitis C.

The present invention is also concerned with a method of treating apatient suspected of having hepatitis C infection by administering tothe patient a combination of any of the compositions of the inventionand an antiviral agent. In various embodiments, the composition and theantiviral agent are administered simultaneously, sequentially, oralternatively.

In one embodiment, the antiviral agent is ribavirin.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. All publications, patent applications,patents, and other references mentioned herein are incorporated byreference in their entirety. In case of conflict, the presentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

Other features and advantages of the invention will be apparent from thefollowing detailed description, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further understood from the followingdescription with reference to the tables, in which:

FIG. 1 is a reducing SDS-PAGE gel showing the purity of unmodifiedIFN-β-1a and 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a:Lane A: molecular weight markers (from top to bottom; 100 kDa, 68 kDa,45 kDa, 27 kDa, and 18 kDa, respectively); Lane B: 4 μg of unmodifiedIFN-β-1a; Lane C: 4 μg of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a.

FIG. 2 depicts traces of the size exclusion chromatography of unmodifiedIFN-β-1a and 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a:Panel A: molecular weight standards; Panel B: 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a; Panel C, unmodifiedIFN-β-1a.

FIG. 3 is a trace of the size exclusion chromatography of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a.

FIG. 4 is a reducing SDS-PAGE gel showing the purity of unmodifiedIFN-β-1a and 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a: LaneA: 2.5 μg of 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a; LaneB: 2.5 μg of unmodified IFN-β-1a; Lane C: molecular weight markers (fromtop to bottom; 100 kDa, 68 kDa, 45 kDa, 27 kDa, and 18 kDa,respectively).

FIG. 5 depicts traces of the size exclusion chromatography of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a; Panel A: molecular weightstandards; Panel B: 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a.

FIG. 6 is a reducing SDS-PAGE gel depicting the stability of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a: Lane A: molecular weightmarkers (from top to bottom; 100 kDa, 68 kDa, 45 kDa, 27 kDa, 18 kDa,and 15 kDa, respectively); Lanes B, C, D, and E: 2 μg of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a removed for assay at day0, 2, 5, and 7, respectively.

FIGS. 7A-B show the antiviral activity of various PEGylated humanIFN-β-1a samples as a function of protein concentration: FIG. 7A;unmodified IFN-β-1a (ο), 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a (□), 20 kDamPEG-O-p-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a (Δ),and 20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified (⋄).FIG. 7B; unmodified IFN-β-1a (ο), 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a (□), 20 kDamPEG-O-p-phenylpropionaldehyde-modified IFN-β-1a (Δ), and 20 kDamPEG-O-m-phenylacetaldehyde-modified IFN-β-1a (⋄).

FIGS. 8 A-B are graphs depicting the pharmacokinetics of unmodified andvarious PEGylated human IFN-β-1a samples: FIG. 8A: Unmodified IFN-β-1a(upper panel) and IFN-13-1a modified with 20 kDamPEG-O-2-methylpropionaldehyde (lower panel); FIG. 8B: IFN-13-1amodified with 20 kDa mPEG-O-p-methylphenyl-O-2-methylpropionaldehyde(upper panel) and 20 kDa mPEG-O-p-phenylacetaldehyde (lower panel).

FIGS. 9 A-B are graphs depicting the pharmacokinetics of unmodified andvarious PEGylated human IFN-β-1a samples: FIG. 9A: Unmodified IFN-β-1a(upper panel) and IFN-β-1a modified with 20 kDamPEG-O-p-phenylpropionaldehyde (lower panel); FIG. 9B: IFN-β-1a modifiedwith 20 kDa mPEG-O-m-phenylacetaldehyde (upper panel) and 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde (lower panel).

FIG. 10 is a bar graph comparing a single administration of 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a, with dailyadministration of unmodified IFN-β-1a at reducing the number ofradially-oriented neovessels in nu/nu mice carrying SK-MEL-1 humanmalignant melanoma cells: treatment with vehicle control once on day 1only (bar A); treatment with 1 MU (5 μg) of unmodified IFN-β-1a daily ondays 1-9 inclusive (bar B); treatment with 1 MU (10 μg) of 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-13-1a once on day 1 only(bar C); and treatment with vehicle control daily on days 1-9 inclusive(bar D).

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to compounds and methods useful in thetreatment of various diseases and disorders. As explained in detailbelow, such diseases and disorders include, in particular, those whichare susceptible to treatment with interferon therapy, including but notlimited to viral infections such as hepatitis infections and autoimmunediseases such as multiple sclerosis.

The compounds of the invention include novel, activated polyalkyleneglycol compounds according to Formula I:

where P is a water soluble polymer such as a polyalkylene glycolpolymer. A non-limiting list of such polymers include other polyalkyleneoxide homopolymers such as polypropylene glycols, polyoxyethylenatedpolyols, copolymers thereof and block copolymers thereof. Other examplesof suitable water-soluble and non-peptidic polymer backbones includepoly(oxyethylated polyol), poly(olefinic alcohol),poly(vinylpyrrolidone), poly(hydroxypropylmethacrylamide),poly(α-hydroxy acid), poly(vinyl alcohol), polyphosphazene,polyoxazoline, poly(N-acryloylmorpholine) and copolymers, terpolymers,and mixtures thereof. In one embodiment, the polymer backbone ispoly(ethylene glycol) or monomethoxy polyethylene glycol (mPEG) havingan average molecular weight from about 200 Da to about 400,000 Da. Itshould be understood that other related polymers are also suitable foruse in the practice of this invention and that the use of the term PEGor poly(ethylene glycol) is intended to be inclusive and not exclusivein this respect. The term PEG includes poly(ethylene glycol) in any ofits forms, including alkoxy PEG, difunctional PEG, multi-armed PEG,forked PEG, branched PEG, pendent PEG, or PEG with degradable linkagestherein.

In the class of compounds represented by Formula I, there are betweenzero and five methylene groups between Y and the Z-containing carbon(e.g., n is zero or an integer from one to five) and m is zero or one,e.g., Y is present or absent.

X and Y are, independently, O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′,or NR′. In some embodiments, X and Y are oxygen.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. The substituentscan be halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonamido, sulfonyl, heterocyclyl,aralkyl, aromatic moiety, heteroaromatic moiety, imino, sulfamoyl,sulfonate, silyl, ether, or alkylthio.

The Z substituent is hydrogen, a straight- or branched-chain, saturatedor unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturatedor unsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group. The substituents can be halogen, hydroxyl,carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl, thioester,thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate,amino, amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, sulfamoyl, sulfonate,silyl, ether, or alkylthio.

When X or Y is NR′, R′ can be hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, a C₃ toC₈ saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl, wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group. The substituents can behalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,sulfamoyl, sulfonate, silyl, ether, or alkylthio.

R is a reactive functional group, i.e., an activating moiety capable ofreacting to form a linkage or a bond between the compound of Formula Iand a biologically-active compound or precursor thereof. Thus, Rrepresents the “activating group” of the activated polyalkylene glycolcompounds (PGCs) represented by Formula I. R can be, for example, acarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,or glyoxal. In particular embodiments, R is an aldehyde hydrate.

Specific examples of R in the literature include N-succinimidylcarbonate (see e.g., U.S. Pat. Nos. 5,281,698, 5,468,478), amine (seee.g., Buckmann et al. Makromol. Chem. 182:1379 (1981), Zaplipsky et al.Eur. Polym. J. 19:1177 (1983)), hydrazide (See, e.g., Andresz et al.Makromol. Chem. 179:301 (1978)), succinimidyl propionate andsuccinimidyl butanoate (see, e.g. Olson et al. in Poly(ethylene glycol)Chemistry & Biological Applications, pp 170-181, Harris & ZaplipskyEds., ACS, Washington, D.C., 1997; see also U.S. Pat. No. 5,672,662),succinimidyl succinate (See. e.g., Abuchowski et al. Cancer Biochem.Biophys. 7:175 (1984) and Joppich et al. Macrolol. Chem. 180:1381(1979), succinimidyl ester (see, e.g., U.S. Pat. No. 4,670,417),benzotriazole carbonate (see, e.g., U.S. Pat. No. 5 5,650,234), glycidylether (see, e.g., Pitha et al. Eur. J. Biochem. 94:11 (1979), Elling etal., Biotech. Appl. Biochem. 13:354 (1991), oxycarbonylimidazole (see,e.g. Beauchamp, et al., Anal. Biochem. 131:25 (1983). Tondelli et al. J.Controlled Release 1:251 (1985)), p-nitrophenyl carbonate (see, e.g.,Veronese, et al., Appl. Biochem. Biotech., 11:141 (1985); and Sartore etal., Appl. Biochem. Biotech. 27:45 10 (1991)), aldehyde (see, e.g.,Harris et al. J. Polym. Sci. Chem. Ed. 22:341 (1984), U.S. Pat. No.5,824,784, U.S. Pat. No. 5,252,714), maleimide (see, e.g., Goodson etal. Bio/Technology 8:343 (1990), Romani et al. in Chemistry of Peptidesand Proteins 2:29 (1984)), and Kogan, Synthetic Comm. 22:2417 (1992)),orthopyridyl-disulfide (see, e.g., Woghiren, et al. Bioconj. Chem. 4:314(1993)), acrylol (see, e.g., Sawhney 15 et al., Macromolecules, 26:581(1993)), vinylsulfone (see, e.g., U.S. Pat. No. 5,900,461). In addition,two molecules of the polymer of this invention can also be linked to theamino acid lysine to form a di-substituted lysine, which can then befurther activated with N-hydroxysuccinimide to form an activeN-succinimidyl moiety (see, e.g., U.S. Pat. No. 5,932,462).

The terms “functional group”, “active moiety”, “active group”,“activating group”, “activating moiety”, “reactive site”,“chemically-reactive group” and” chemically-reactive moiety” are used inthe art and herein to refer to distinct, definable portions or units ofa molecule. The terms are somewhat synonymous in the chemical arts andare used herein to indicate the portions of molecules having acharacteristic chemical activity and which are typically reactive withother molecules. The term “active,” when used in conjunction withfunctional groups, is intended to include those functional groups thatreact readily with electrophilic or nucleophilic groups on othermolecules, in contrast to those groups that require strong catalysts orhighly impractical reaction conditions in order to react. For example,as would be understood in the art, the term “active ester” would includethose esters that react readily with nucleophilic groups such as amines.Typically, an active ester will react with an amine in aqueous medium ina matter of minutes, whereas certain esters, such as methyl or ethylesters, require a strong catalyst in order to react with a nucleophilicgroup.

In the compounds of the invention as defined above, the functional groupR becomes a linking moiety, R*, after it has reacted with abiologically-active molecule to form a linkage or bond between theactivated polyalkylene glycol compound (PGC) and the biologically-activecompound. Thus, B is a biologically-active compound after conjugation tothe PGC and R* is a moiety formed by the reaction of R on the activatedPGC with one or more reactive functional groups on thebiologically-active compound, B, such that a single covalent attachmentresults between the PGC and biologically-active compound. In a preferredembodiment, R* is a moiety formed by the reaction of R on the activatedPGC with a single reactive functional group on the biologically-activecompound, such that a covalent attachment results between the activatedpolyalkylene glycol compound (PGC) and the biologically-active compound.

The biologically-active compound or precursor thereof (B) is preferablynot adversely affected by the presence of the PGC. Additionally, Beither naturally has a functional group which is able to react with andform a linkage with the activated PGC, or is modified to contain such areactive group.

As used herein, a precursor of B is an inactive or less active form of Bthat changes to the active or more active form, respectively, uponcontact with physiological conditions, e.g., administration to asubject. Such changes can be conformational or structural changes,including, but not limited to, changing from a protected form to anon-protected form of B. As used herein, such change does not includerelease of the conjugated PGCs of this invention.

As would be understood in the art, the term “protected” refers to thepresence of a protecting group or moiety that prevents reaction of thechemically-reactive functional group under certain reaction conditions.The protecting group will vary depending on the type ofchemically-reactive group being protected. For example, if thechemically-reactive group is an amine or a hydrazide, the protectinggroup can be selected from the group of tert-butyloxycarbonyl (t-Boc)and 9-fluorenylmethoxycarbonyl (Fmoc). If the chemically-reactive groupis a thiol, the protecting group can be orthopyridyldisulfide. If thechemically-reactive group is a carboxylic acid, such as butanoic orpropionic acid, or a hydroxyl group, the protecting group can be benzylor an alkyl group such as methyl or ethyl. Other protecting groups knownin the art may also be used in the invention.

The terms “linking moiety”, “linkage” or “linker” are used herein torefer to moieties or bonds that are formed as the result of a chemicalreaction and typically are covalent linkages. Thus, the linkagerepresented by bond R*-B in the above formulae results from the reactionbetween an activated moiety, R, on the PGC with a biologically-activecompound, i.e., B′. R* is the linking moiety formed from R upon reactionwith B′, and B is the biologically-active compound as conjugated to thePGC by reaction of a functional group on B′ with R.

As used herein, the term “biologically-active compound” refers to thosecompounds that exhibit one or more biological responses or actions whenadministered to a subject and contain reactive groups that containreactive moieties that are capable of reacting with and conjugating toat least one activated PGC of the invention. The term“biologically-active molecule”, “biologically-active moiety” or“biologically-active agent” when used herein means any substance whichcan affect any physical or biochemical properties of any subject,including but not limited to viruses, bacteria, fungi, plants, animals,and humans. In particular, as used herein, biologically-active moleculesinclude any substance intended for diagnosis, cure, mitigation,treatment, or prevention of disease in humans or other animals, or tootherwise enhance physical or mental well-being of humans or animals.

Examples of biologically-active molecules include, but are not limitedto, peptides, peptide analogs, proteins, enzymes, small molecules, dyes,lipids, nucleosides, oligonucleotides, analogs of oligonucleotides,sugars, oligosaccharides, cells, viruses, liposomes, microparticles,surfaces and micelles.

Classes of biologically-active agents that are suitable for use with theinvention include, but are not limited to, chemokines, lymphokines,antibodies, soluble receptors, anti-tumor agents, anti-anxiety agents,hormones, growth factors, antibiotics, fungicides, fungistatic agents,anti-viral agents, steroidal agents, antimicrobial agents, germicidalagents, antipyretic agents, antidiabetic agents, bronchodilators,antidiarrheal agents, coronary dilation agents, glycosides,spasmolytics, antihypertensive agents, antidepressants, antianxietyagents, other psychotherapeutic agents, corticosteroids, analgesics,contraceptives, nonsteroidal anti-inflammatory drugs, blood glucoselowering agents, cholesterol lowering agents, anticonvulsant agents,other antiepileptic agents, immunomodulators, anticholinergics,sympatholytics, sympathomimetics, vasodilatory agents, anticoagulants,antiarrhythmics, prostaglandins having various pharmacologic activities,diuretics, sleep aids, antihistaminic agents, antineoplastic agents,oncolytic agents, antiandrogens, antimalarial agents, antileprosyagents, and various other types of drugs. See Goodman and Gilman's TheBasis of Therapeutics (Ninth Edition, Pergamon Press, Inc., USA, 1996)and The Merck Index (Thirteenth Edition, Merck & Co., Inc., USA, 2001),each of which is incorporated herein by reference.

Biologically-active compounds include any compound that exhibits abiological response in its present form, or any compound that exhibits abiological response as a result of a chemical conversion of itsstructure from its present form. For example, biologically-activecompounds will include any compound that contains a protective groupthat, when cleaved, results in a compound that exhibits a biologicalresponse. Such cleavage can be the result, for example, of an in vivoreaction of the compound with endogenous enzymes or a pre-administrationreaction of the compound, including its reaction with the activated PGCsof this invention. As a further example, biologically-active compoundswill also include any compound which undergoes a stereotransformation,in vivo or ex vivo, to form a compound that exhibits a biologicalresponse or action.

Biologically-active compounds typically contain several reactive sitesat which covalent attachment of the activated PGC is feasible. Forexample, amine groups can undergo acylations, sulfhydryl groups canundergo addition reactions and alkylations, carbonyl and carboxyl groupscan undergo acylations, and aldehyde and hydroxyl groups can undergoamination and reductive amination. One or more of these reactions can beused in the preparation of the polyalkylene glycol-modifiedbiologically-active compounds of the invention. In addition,biologically-active compounds can be modified to form reactive moietieson the compound that facilitate such reactions and the resultantconjugation to the activated PGC.

Those of ordinary skill will recognize numerous reaction mechanismsavailable to facilitate conjugation of the activated PGC to abiologically-active compound. For example, when the activating moiety,R, is a hydrazide group, it can be covalently coupled to sulfhydryl,sugar, and carbonyl moieties on the biologically-active compounds (afterthese moieties undergo oxidation to produce aldehydes). The reaction ofhydrazide activating moieties (R) with aldehydes on biologically-activecompounds (B′) creates a hydrazone linkage (R*-B). When R is a maleimidegroup, it can be reacted with a sulfhydryl group to form a stablethioether linkage. If sulfhydryls are not present on thebiologically-active compound, they may be created through disulfidereduction or through thiolation with 2-iminothiolane or SATA. When R isan imidoester it will react with primary amines on B′ to form animidoamide linkage. Imidoester conjugation is usually performed betweenpH 8.5-9.0. When connecting the activated PGCs to biologically-activeproteins, imidoesters provide an advantage over other R groups sincethey do not affect the overall charge of the protein. They carry apositive charge at physiological pH, as do the primary amines theyreplace. Imidoester reactions are carried out between 0° C. and roomtemperature (e.g., at 4° C.), or at elevated temperatures underanhydrous conditions. When R is an NHS-ester, its principal target isprimary amines. Accessible α-amine groups, for example those present onthe N-termini of peptides and proteins, react with NHS-esters to form acovalent amide bond.

In some embodiments, R*-B is a hydrolytically-stable linkage. Ahydrolytically stable linkage means that the linkage is substantiallystable in water and does not react with water at useful pHs, e.g., thelinkage is stable under physiological conditions for an extended periodof time, perhaps even indefinitely. In other embodiments, R*-B is ahydrolytically-unstable or degradable linkage. A hydrolytically-unstablelinkage means that the linkage is degradable in water or in aqueoussolutions, including for example, blood. Enzymatically-unstable ordegradable linkages also means that the linkage can be degraded by oneor more enzymes.

As understood in the art, polyalkylene and related polymers may includedegradable linkages in the polymer backbone or in the linker groupbetween the polymer backbone and one or more of the terminal functionalgroups of the PGC molecule. For example, ester linkages formed by thereaction of, e.g., PGC carboxylic acids or activated PGC carboxylicacids with alcohol groups on a biologically-active compound generallyhydrolyze under physiological conditions to release the agent. Otherhydrolytically-degradable linkages include carbonate linkages; iminelinkages resulted from reaction of an amine and an aldehyde (See, e.g.,Ouchi et al., Polymer Preprints, 38(1):582-3 (1997)); phosphate esterlinkages formed by reacting an alcohol with a phosphate group; acetallinkages that are the reaction product of an aldehyde and an alcohol;orthoester linkages that are the reaction product of a formate and analcohol; peptide linkages formed by an amine group, e.g., at an end of athe PGC, and a carboxyl group of a peptide; and oligonucleotide linkagesformed by a phosphoramidite group, e.g., at the end of a polymer, and a5′ hydroxyl group of an oligonucleotide.

The polyalkylene glycol, P, can be polyethylene glycol, having thestructure of Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwherein a is an integer from 4 to 10,000 and E is hydrogen or astraight- or branched-chain C₁ to C₂₀ alkyl group, a detectable label,or a moiety suitable for forming a bond between the compound of FormulaI and a biologically-active compound or precursor thereof.

Thus, when E is a moiety suitable for forming a bond between thecompound of Formula I and a biologically-active compound or precursorthereof, E can be a carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or glyoxal. It is tobe understood that E should be compatible with R so that reactionbetween E and R does not occur.

By “detectable label” is meant any label capable of detection.Non-limiting examples include radioactive isotopes, fluorescentmoieties, phosphorescent moieties, chemiluminescent moieties, andquantum dots. Other detectable labels include biotin, cysteine,histidine, haemagglutinin, myc or flag tags.

In some embodiments, E has the structure according to Formula III orFormula IV:

Each Q, X, Y, Z, m, and n are as defined above, and each W is,independently, hydrogen or a C₁ to C₇ alkyl.

In this class of compounds, R″ is a moiety suitable for forming a bondbetween the compound of Formula III and a biologically-active compoundor precursor thereof; and R′″ is a moiety suitable for forming a bondbetween the compound of Formula IV and a biologically-active compound orprecursor thereof.

R″ and R′″ can be of carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or glyoxal. It is tobe understood that R″ and

R′″ should be compatible with R so that reaction with R does not occur.

As used herein, R″ and R′″ upon conjugation to a biologically-activecompound or precursor thereof, form linking moieties as defined above.Thus, R** is a linking moiety formed by the reaction of the R″ or R′″group on the activated PGC with a reactive functional group on thebiologically-active compound, such that a covalent attachment resultsbetween the PGC and the biologically-active compound. R and R″ or R′″can be the same moiety or different moieties, and thebiologically-active compound bound to each can be the same or different.

As used herein, the term “alkyl” refers to the radical of saturatedaliphatic groups, including straight-chain alkyl groups, branched-chainalkyl groups, cycloalkyl (alicyclic) groups, alkyl substitutedcycloalkyl groups, and cycloalkyl substituted alkyl groups. In preferredembodiments, a straight chain or branched chain alkyl has 30 or fewercarbon atoms in its backbone (e.g., C₁-C₃₀ for straight chain, C₃-C₃₀for branched chain), and more preferably 20 or fewer. Likewise,preferred cycloalkyls have from 3-10 carbon atoms in their ringstructure, and more preferably have 5, 6, or 7 carbons in the ringstructure.

Moreover, the term “alkyl” (or “lower alkyl”) is intended to includeboth “unsubstituted alkyls” and “substituted alkyls”, the latter ofwhich refers to alkyl moieties having substituents replacing a hydrogenon one or more carbons of the hydrocarbon backbone. Such substituentscan include, for example, a halogen, a hydroxyl, a carbonyl (such as acarboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (suchas a thioester, a thioacetate, or a thioformate), an alkoxyl, aphosphoryl, a phosphonate, a phosphinate, an amino, an amido, anamidine, an imine, a cyano, a nitro, an azido, a sulfhydryl, analkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, asulfonyl, a heterocyclyl, an aralkyl, or an aromatic or heteroaromaticmoiety. It will be understood by those skilled in the art that themoieties substituted on the hydrocarbon chain can themselves besubstituted, if appropriate. For instance, the substituents of asubstituted alkyl may include substituted and unsubstituted forms ofamino, azido, imino, amido, phosphoryl (including phosphonate andphosphinate), sulfonyl (including sulfate, sulfonamido, sulfamoyl, andsulfonate), and silyl groups, as well as ethers, alkylthios, carbonyls(including ketones, aldehydes, carboxylates, and esters), —CF₃, —CN andthe like. Cycloalkyls can be further substituted with alkyls, alkenyls,alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls, —CF₃,—CN, and the like.

The term “aralkyl”, as used herein, refers to an alkyl group substitutedwith an aryl group (e.g., an aromatic or heteroaromatic group).Exemplary aralkyl groups include, but are not limited to, benzyl andmore generally (CH₂)_(n)Ph, where Ph is phenyl or substituted phenyl,and n is 1, 2, or 3.

The terms “alkenyl” and “alkynyl” refer to unsaturated aliphatic groupsanalogous in length and possible substitution to the alkyls describedabove, but that contain at least one double or triple bond,respectively.

Unless the number of carbons is otherwise specified, “lower alkyl” asused herein means an alkyl group, as defined above, but having from oneto ten carbons, more preferably from one to six carbon atoms in itsbackbone structure. Likewise, “lower alkenyl” and “lower alkynyl” havesimilar chain lengths. Preferred alkyl groups are lower alkyls. Inpreferred embodiments, a substituent designated herein as alkyl is alower alkyl.

The term “aryl” as used herein includes 5-, 6-, and 7-memberedsingle-ring aromatic groups that may include from zero to fourheteroatoms, for example, benzene, pyrrole, furan, thiophene, imidazole,oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine, pyridazineand pyrimidine, and the like. Those aryl groups having heteroatoms inthe ring structure may also be referred to as “aryl heterocycles” or“heteroaromatics.” The aromatic ring can be substituted at one or morering positions with such substituents as described above, for example,halogen, azide, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl,alkoxyl, amino, nitro, sulfhydryl, imino, amido, phosphonate,phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio, sulfonyl,sulfonamido, ketone, aldehyde, ester, heterocyclyl, aromatic orheteroaromatic moieties, —CF₃, —CN, or the like. The term “aryl” alsoincludes polycyclic ring systems having two or more cyclic rings inwhich two or more carbons are common to two adjoining rings (the ringsare “fused rings”) wherein at least one of the rings is aromatic, e.g.,the other cyclic rings can be cycloalkyls, cycloalkenyls, cycloalkynyls,aryls, and/or heterocyclyls.

The terms ortho, meta and para apply to 1,2-, 1,3-, and1,4-disubstituted benzenes, respectively. For example, the names1,2-dimethylbenzene and ortho-dimethylbenzene are synonymous.

The terms “heterocyclyl” or “heterocyclic group” refer to 3- to10-membered ring structures, more preferably 3- to 7-membered rings,whose ring structures include one to four heteroatoms. Heterocycles canalso be polycycles. Heterocyclyl groups include, for example, thiophene,thianthrene, furan, pyran, isobenzofuran, chromene, xanthene,phenoxathiin, pyrrole, imidazole, pyrazole, isothiazole, isoxazole,pyridine, pyrazine, pyrimidine, pyridazine, indolizine, isoindole,indole, indazole, purine, quinolizine, isoquinoline, quinoline,phthalazine; naphthyridine, quinoxaline, quinazoline, cinnoline,pteridine, carbazole, carboline, phenanthridine, acridine, pyrimidine,phenanthroline, phenazine, phenarsazine, phenothiazine, furazan,phenoxazine, pyrrolidine, oxolane, thiolane, oxazole, piperidine,piperazine, morpholine, lactones, lactams such as azetidinones andpyrrolidinones, sultams, sultones, and the like. The heterocyclic ringcan be substituted at one or more positions with substituents asdescribed above, such as, for example, halogen, alkyl, aralkyl, alkenyl,alkynyl, cycloalkyl, hydroxyl, amino, nitro, sulfhydryl, imino, amido,phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio,sulfonyl, ketone, aldehyde, ester, a heterocyclyl, an aromatic orheteroaromatic moiety, —CF₃, —CN, or the like.

The term “carbocycle”, as used herein, refers to an aromatic ornon-aromatic ring in which each atom of the ring is carbon.

Heterocycles and carbocycles include fused bicyclic and bridged bicyclicring structures.

As used herein, the term “nitro” means —NO₂; the term “halogen”designates —F, —Cl, —Br or —I; the term “sulfhydryl” means —SH; the term“hydroxyl” means —OH; and the term “sulfonyl” means —SO₂—.

The terms “amine” and “amino” are art-recognized and refer to bothunsubstituted and substituted amines, e.g., a moiety that can berepresented by the general formula:

wherein R₉, R₁₀ and R′₁₀ each independently represent a hydrogen, analkyl, an alkenyl, —(CH₂)_(m)—R₈, or R₉ and R₁₀ taken together with theN atom to which they are attached complete a heterocycle having from 4to 8 atoms in the ring structure; R₈ represents an aryl, a cycloalkyl, acycloalkenyl, a heterocycle or a polycycle; and m is zero or an integerin the range of 1 to 8.

The term “alkylamine” as used herein means an amine group, as definedabove, having a substituted or unsubstituted alkyl attached thereto,i.e., at least one of R₉ and R₁₀ is an alkyl group.

The term “acylamino” is art-recognized and refers to a moiety that canbe represented by the general formula:

wherein R₉ is as defined above, and R′₁₁ represents a hydrogen, analkyl, an alkenyl or —(CH₂)_(m)—R₈, where m and R₈ are as defined above.

The term “amido” is art-recognized as an amino-substituted carbonyl andincludes a moiety that can be represented by the general formula:

wherein R₉, R₁₀ are as defined above. Preferred embodiments of the amidewill not include imides which may be unstable.

The term “amidine” is art-recognized as a group that can be representedby the general formula:

wherein R₉, R₁₀ are as defined above.

The term “guanidine” is art-recognized as a group that can berepresented by the general formula:

wherein R₉, R₁₀ are as defined above.

The term “alkylthio” refers to an alkyl group, as defined above, havinga sulfur radical attached thereto. In preferred embodiments, the“alkylthio” moiety is represented by one of —S-alkyl, —S-alkenyl,—S-alkynyl, and —S—(CH₂)_(m)—R₈, wherein m and R₈ are defined above.Representative alkylthio groups include methylthio, ethylthio, and thelike.

The term “carbonyl” is art-recognized and includes moieties that can berepresented by the general formula:

wherein X is a bond or represents an oxygen or a sulfur, and R₁₁represents a hydrogen, an alkyl, an alkenyl, —(CH₂)_(m)—R₈ or apharmaceutically-acceptable salt, R′₁₁ represents a hydrogen, an alkyl,an alkenyl or —(CH₂)_(m)—R₈, where m and R₈ are as defined above. WhereX is an oxygen and R₁₁ or R′₁₁ is not hydrogen, the formula representsan “ester”. Where X is an oxygen, and R₁₁ is as defined above, themoiety is referred to herein as a carboxyl group, and particularly whenR₁₁ is a hydrogen, the formula represents a “carboxylic acid”. Where Xis an oxygen, and R′₁₁ is hydrogen, the formula represents a “formate”.In general, where the oxygen atom of the above formula is replaced bysulfur, the formula represents a “thiolcarbonyl” group. Where X is asulfur and R₁₁ or R′₁₁ is not hydrogen, the formula represents a“thioester.” Where X is a sulfur and R₁₁ is hydrogen, the formularepresents a “thiocarboxylic acid.” Where X is a sulfur and R′₁₁ ishydrogen, the formula represents a “thioformate.” On the other hand,where X is a bond, and R₁₁ is not hydrogen, the above formula representsa “ketone” group. Where X is a bond, and R₁₁ is hydrogen, the aboveformula represents an “aldehyde” group.

The terms “alkoxyl” or “alkoxy” as used herein refers to an alkyl group,as defined above, having an oxygen radical attached thereto.Representative alkoxyl groups include methoxy, ethoxy, propyloxy,tert-butoxy, and the like. An “ether” is two hydrocarbons covalentlylinked by an oxygen. Accordingly, the substituent of an alkyl thatrenders that alkyl an ether is or resembles an alkoxyl, such as can berepresented by one of —O-alkyl, —O-alkenyl, —O-alkynyl, —O-(CH₂)_(m)—R₈,where m and R₈ are described above.

The term “sulfonate” is art-recognized and includes a moiety that can berepresented by the general formula:

in which R₄₁ is an electron pair, hydrogen, alkyl, cycloalkyl, or aryl.

The term “sulfate” is art recognized and includes a moiety that can berepresented by the general formula:

in which R₄₁ is as defined above.

The term “sulfonamido” is art recognized and includes a moiety that canbe represented by the general formula:

in which R₉ and R′₁₁ are as defined above.

The term “sulfamoyl” is art-recognized and includes a moiety that can berepresented by the general formula:

in which R₉ and R₁₀ are as defined above.

The term “sulfonyl”, as used herein, refers to a moiety that can berepresented by the general formula:

in which R₄₄ is selected from the group consisting of hydrogen, alkyl,alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl.

The term “sulfoxido” as used herein, refers to a moiety that can berepresented by the general formula:

in which R₄₄ is selected from the group consisting of hydrogen, alkyl,alkenyl, alkynyl, cycloalkyl, heterocyclyl, aralkyl, or aryl.

It will be understood that “substitution” or “substituted with” includesthe implicit proviso that such substitution is in accordance withpermitted valence of the substituted atom and the substituent, and thatthe substitution results in a stable compound, e.g., which does notspontaneously undergo transformation such as by rearrangement,cyclization, elimination, etc.

As used herein, the term “substituted” is contemplated to include allpermissible substituents of organic compounds. In a broad aspect, thepermissible substituents include acyclic and cyclic, branched andunbranched, carbocyclic and heterocyclic, aromatic and nonaromaticsubstituents of organic compounds. Illustrative substituents include,for example, those described herein above. The permissible substituentscan be one or more and the same or different for appropriate organiccompounds. For purposes of this invention, the heteroatoms such asnitrogen may have hydrogen substituents and/or any permissiblesubstituents of organic compounds described herein which satisfy thevalences of the heteroatoms. This invention is not intended to belimited in any manner by the permissible substituents of organiccompounds.

A comprehensive list of the abbreviations utilized by organic chemistsof ordinary skill in the art appears in the first issue of each volumeof the Journal of Organic Chemistry, this list is typically presented ina table entitled Standard List of Abbreviations. The abbreviationscontained in said list, and all abbreviations utilized by organicchemists of ordinary skill in the art are hereby incorporated byreference.

In some embodiments, the compounds of the invention have the structureaccording to Formula V:

X, Y, m, n, Z, and R′ are as defined above, and R is an activatingmoiety as defined above, suitable for forming a bond between thecompound of Formula V and a biologically-active compound or precursor.In particular embodiments, R is an aldehyde hydrate.

P is as defined above, and can be represented by Formula IIE-(O—CH₂CH₂)_(a)—,  Formula II

where E is as described above, and in some embodiments, can berepresented by Formula III or IV.

T₁ and T₂ are, independently, absent, or a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, a C₃ toC₈ saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group, or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group. The substituents can behalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

When d is zero, there are no additional substituents (L) on the aromaticring. When d is an integer from 1 to 4, the substituents (L) can be astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group, C₃ to C₈ saturated or unsaturated cyclic alkyl orcyclic heteroalkyl, a substituted or unsubstituted aryl or heteroarylgroup or a substituted or unsubstituted alkaryl wherein the alkyl is aC₁ to C₂₀ saturated or unsaturated alkyl or heteroalkaryl group. Thesubstituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

When R is an aldehyde, the compounds fall within those represented byFormula VI:

where all other variables are as defined above.

For example, when X and Y are oxygen and R is an aldehyde, the compoundsof the invention are represented by compound J.

where the T₁ and T₂ substituents can be in the ortho, meta, or paraarrangement.

Where the T₁ and T₂ substituents are straight-chain alkyl groups, and dis zero, the compounds are represented by Formula IX:

where each u is independently zero or an integer from one to five andall other variables are as defined above. In particular embodiments, Zis hydrogen or methyl.

Particular classes of compounds falling within Formula IX can berepresented by Formulae VII and VIII:

Some representative activated polyalkylene glycol compounds include thefollowing, where the polyalkylene glycol polymer is PEG or mPEG:

In some embodiments, the compounds of the invention are represented byFormula X:

where, as above, n is zero or an integer from one to five, and X is O,S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′.

When X is NR′, R′ can be hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, oralkylthio. Z can be a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group. When present, the substituents can be halogen,hydroxyl, carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl,thioester, thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate,phosphinate, amino, amido, amidine, imine, cyano, nitro, azido,sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

As defined above, R is an activating moiety suitable for forming a bondbetween the compound of Formula X and a biologically-active compound orprecursor thereof. In some embodiments, R is an aldehyde hydrate.

P is a polyalkylene glycol polymer as defined above, and can berepresented by Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

where E and a are as described above, and in some embodiments, can berepresented by Formula III or IV. In some embodiments, E is methyl, and,therefore, P is mPEG.

When R is an aldehyde and X is oxygen, the compounds fall within thestructure according to Formula XI:

where P, Z and n are as defined for Formula X.

When P is mPEG, the compounds are described by Formula XII:

and when n is one and Z is methyl, the compound is represented byFormula XIII:

wherein a is an integer from 4 to 10,000.

Examples of synthetic pathways for making compounds according to theinvention are set forth in the Examples below.

The invention also includes compositions of the activated polyalkyleneglycol compounds (PGCs) of the invention and one or morebiologically-active compounds. As described above, biologically-activecompounds are those compounds that exhibit a biological response oraction when administered to a subject. Unconjugated biologically-activecompounds may be administered to a subject in addition to the compoundsof the invention. Additionally, biologically-active compounds maycontain reactive groups that are capable of reacting with andconjugating to at least one activated PGC of the invention.

The invention also includes conjugates of the novel PGCs withbiologically-active compounds. In one embodiment, the conjugates areformed from a compound of Formula I and a biologically-active compound(B) and are described according to Formula XIV:

As above, m is zero or one so that Y is present or absent, n is zero oran integer from one to five, and X and Y are independently O, S, CO,CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. When present, thesubstituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

Each R′ and Z is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein the substituents areselected from the group consisting of halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, andalkylthio;

R* is a linking moiety formed from the reaction of R with acorresponding functional group on the biologically-active compound, B,as described above. For example, R* is formed from the reaction of amoiety such as a carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or glyoxalfunctionality with a biologically-active compound or precursor thereof.

P is a polyalkylene glycol polymer as defined above, and can berepresented by Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

where E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkyl group(e.g., methyl), a detectable label, or a moiety suitable for forming abond between the compound of Formula XIV and a biologically-activecompound or precursor thereof. As above, a is an integer from 4 to10,000.

Where E is a detectable label, the label can be, for example, aradioactive isotope, a fluorescent moiety, a phosphorescent moiety, achemiluminescent moiety, or a quantum dot.

When E is a moiety suitable for forming a bond between the compound ofFormula XIV and a biologically-active compound or precursor thereof, Ecan form a bond to another molecule of the biologically-active compound(B) so that the activated polyalkylene glycol compound is bound ateither terminus to a molecule of the same type of biologically-activecompound, to produce a dimer of the molecule.

In some embodiments, E forms a bond to a biologically-active compoundother than B, creating a heterodimer of biologically-active compounds orprecursors thereof.

In other embodiments, E forms an additional bond to thebiologically-active compound, B, such that both E and R are boundthrough different functional groups of the same molecule of thebiologically-active compound or precursor thereof.

When E is capable of forming a bond to a biologically-active molecule orprecursor thereof, E can be the same as or different from R and ischosen from carboxylic acid, ester, aldehyde, aldehyde hydrate, acetal,hydroxy, protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

When E is capable of forming a bond to a biologically-active molecule orprecursor thereof, E can have the structure according to Formula III orFormula IV:

where each Q, X, Y, Z, m, and n are, independently, as defined above,each W is, independently, hydrogen or a C₁ to C₇ alkyl, R″ is a moietysuitable for forming a bond between the compound of Formula III and abiologically-active compound or precursor thereof, and R′″ is a moietysuitable for forming a bond between the compound of Formula IV and abiologically-active compound or precursor thereof.

R″ and R′″ are, independently chosen from carboxylic acid, ester,aldehyde, aldehyde hydrate, acetal, hydroxy, protected hydroxy,carbonate, alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

When Q in Formula XIV is a substituted or unsubstituted alkaryl, theconjugate is formed from an activated polyalkylene glycol of Formula Vand a biologically-active molecule (B), and is described according toFormula XV:

where T₁ and T₂ are, independently, absent, or a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. When present, thesubstituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio. In someembodiments, T₁ and T₂, if present, are straight- or branched-chainsaturated or unsaturated or C₁ to C₂₀ alkyl or heteroalkyl group.

d is zero (e.g., there are no L substituents on the aromatic ring) or aninteger from 1 to 4. Each L is, when present, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. The substituentscan be halogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

All other variables are as described above, including P, which is apolyalkylene glycol polymer, and can be represented by Formula II:E-(O—CH₂CH₂)_(a)—,  Formula IIwhere E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkyl group(e.g., methyl), a detectable label, or a moiety suitable for forming abond between the compound of Formula XV and a biologically-activecompound or precursor thereof. As above, a is an integer from 4 to10,000.

Where E is a detectable label, the label can be, for example, aradioactive isotope, a fluorescent moiety, a phosphorescent moiety, achemiluminescent moiety, or a quantum dot.

When E is a moiety suitable for forming a bond between the compound ofFormula XV, and a biologically-active compound, B, E can form a bond toanother molecule of the biologically-active compound (B) so that theactivated polyalkylene glycol compound is bound at either terminus to amolecule of the same type of biologically-active compound, to produce adimer of the molecule.

In some embodiments, E forms a bond to a biologically-active compoundother than B, creating a heterodimer of biologically-active compounds orprecursors thereof.

In other embodiments, E forms an additional bond to thebiologically-active compound, B, such that both E and R are boundthrough different functional groups of the same molecule of thebiologically-active compound or precursor thereof.

When E is capable of forming a bond to a biologically-active molecule orprecursor thereof, E can be the same as or different from R and ischosen from carboxylic acid, ester, aldehyde, aldehyde hydrate, acetal,hydroxy, protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

When E can form a bond with a biologically-active compound or precursorthereof, in some embodiments, E can be Formula III or Formula IV:

where each Q, X, Y, Z, m, and n are, independently, as defined above,each W is, independently, hydrogen or a C₁ to C₇ alkyl, R″ is a moietysuitable for forming a bond between the compound of Formula III and abiologically-active compound or precursor thereof, and R′″ is a moietysuitable for forming a bond between the compound of Formula IV and abiologically-active compound or precursor thereof.

R″ and R′″ are, independently chosen from carboxylic acid, ester,aldehyde, aldehyde hydrate, acetal, hydroxy, protected hydroxy,carbonate, alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

When bound at both ends to a biologically-active compound or precursorthereof, these bifunctional molecules can be represented according toFormula XX or Formula XXI:

where each X and Y, T₁ and T₂, R′ and Z, L, Q, m, n, a, and n are asdescribed above, and each W is, independently, hydrogen or a C₁ to C₇alkyl. R* and R** are, independently, linking moieties formed from thereaction of R and R″ with a biologically-active compound or precursorthereof, and B and B′ are each a biologically-active compound, orprecursor thereof, after conjugation with R and R″, respectively.

In some embodiments, B and B′ are the same type of biologically-activecompound. In other embodiments, B and B′ are differentbiologically-active compounds. In still other embodiments, B. and B′ arethe same biologically active molecule. In additional embodiments, R* andR** are the same. In other embodiments, R* and R** are different. Forexample, in some embodiments, E can form a bond to another molecule ofthe biologically-active compound (B=B′) so that the activated PGC isbound at either terminus to a molecule of the same type ofbiologically-active compound, to produce a dimer of the molecule. Insome embodiments, E forms a bond to a biologically-active compound otherthan B (B is not B′), creating a heterodimer of biologically-activecompounds or precursors thereof. In other embodiments, E forms anadditional bond to the biologically-active compound, B, such that both E(through R″ or R′″) and R are bound through different functional groupsof the same molecule of the biologically-active compound or precursorthereof.

In some embodiments, R* or R** is methylene group and B or B′ is abiologically-active molecule containing an amino group, where themethylene group forms a bond with the amino group on B. For example, theamine can be the amino terminus of a peptide, an amine of an amino acidside chain of a peptide, or an amine of a glycosylation substituent of aglycosylated peptide. In some embodiments, the peptide is an interferon,such as interferon-beta, e.g., interferon-beta-1a. In some embodiments,this type of bond is formed by a reductive alkylation reaction.

Where the T₁ and T₂ substituents of Formula XV are straight-chain alkylgroups, X and Y are oxygen, and d is zero, the conjugates arerepresented by Formula XIX:

where each u is independently zero or an integer from one to five andall other variables are as defined above. In particular embodiments, Zis hydrogen or methyl.

Particular classes of compounds falling within Formula XV can berepresented by Formulae XVII and XVIII formed from the reaction ofFormulae VII and VIII, respectively, with a biologically-activecompound, or precursor thereof:

where n is zero or an integer from one to five, P is a polyalkyleneglycol polymer, as described above, Z is hydrogen, a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, R* is a linking moiety as described above, B is abiologically-active molecule. These compounds can be bifunctional ormonofunctional, depending on the identity of E, as described above.

In some embodiments, R* is a methylene group and B is abiologically-active molecule containing an amino group, where themethylene group forms a bond with the amino group on B. For example, theamine scan be the amino terminus of a peptide, an amine of an amino acidside chain of a peptide, or an amine of a glycosylation substituent of aglycosylated peptide. In some embodiments, the peptide is an interferon,such as interferon-beta, e.g., interferon-beta-1a. In some embodiments,this type of bond is formed by a reductive alkylation reaction.

The conjugates of the invention can also be formed from reaction ofcompounds according to Formula X with a biologically-active compound orprecursor thereof, to form conjugates according to Formula XXII:

where B is a biologically-active molecule, as described above and n iszero or an integer from one to five.

X is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, or NR′, when X is NR′,R′ is hydrogen, a straight- or branched-chain, saturated or unsaturatedC₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈ saturated or unsaturatedcyclic alkyl or cyclic heteroalkyl, a substituted or unsubstituted arylor heteroaryl group or a substituted or unsubstituted alkaryl whereinthe alkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup. If present, the substituents can be halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, oralkylthio.

Z is a straight- or branched-chain, saturated or unsaturated C₁ to C₂₀alkyl or heteroalkyl group, C₃ to C₉ saturated or unsaturated cyclicalkyl or cyclic heteroalkyl, a substituted or unsubstituted aryl orheteroaryl group or a substituted or unsubstituted alkaryl wherein thealkyl is a C₁ to C₂₀ saturated or unsaturated alkyl or heteroalkarylgroup. The substituents can be halogen, hydroxyl, carbonyl, carboxylate,ester, formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

R* is a linking moiety formed from the reaction of R with acorresponding functional group on the biologically-active compound, B,as described above. For example, R* is formed from the reaction of amoiety such as a carboxylic acid, ester, aldehyde, aldehyde hydrate,acetal, hydroxy, protected hydroxy, carbonate, alkenyl, acrylate,methacrylate, acrylamide, substituted or unsubstituted thiol, halogen,substituted or unsubstituted amine, protected amine, hydrazide,protected hydrazide, succinimidyl, isocyanate, isothiocyanate,dithiopyridine, vinylpyridine, iodoacetamide, epoxide,hydroxysuccinimidyl, azole, maleimide, sulfone, allyl, vinylsulfone,tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl, or glyoxalfunctionality with a biologically-active compound or precursor thereof.

In some embodiments, Z is methyl and n is one.

P is a polyalkylene glycol polymer as defined above, and can berepresented by Formula II:E-(O—CH₂CH₂)_(a)—,  Formula II

where E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkyl group(e.g., methyl), a detectable label, or a moiety suitable for forming abond between the compound of Formula XXII and a biologically-activecompound or precursor thereof. As above, a is an integer from 4 to10,000.

Where E is a detectable label, the label can be, for example, aradioactive isotope, a fluorescent moiety, a phosphorescent moiety, achemiluminescent moiety, or a quantum dot.

When E is capable of forming a bond to a biologically-active molecule orprecursor thereof, a bifunctional molecule results. E can form a bond toanother molecule of the biologically-active compound (B) so that theactivated polyalkylene glycol compound is bound at either terminus to amolecule of the same type of biologically-active compound, to produce adimer of the molecule.

In some embodiments, E forms a bond to a biologically-active compoundother than B, creating a heterodimer of biologically-active compounds orprecursors thereof.

In other embodiments, E forms an additional bond to thebiologically-active compound, B, such that both E and R are boundthrough different functional groups of the same molecule of thebiologically-active compound or precursor thereof.

When E is capable of forming a bond to a biologically-active molecule orprecursor thereof, E can be the same as or different from R and ischosen from carboxylic acid, ester, aldehyde, aldehyde hydrate, acetal,hydroxy, protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

In some embodiments, E can have the structure according to Formula IIIor Formula IV:

where each Q, X, Y, Z, m, and n are, independently, as defined above,each W is, independently, hydrogen or a C₁ to C₇ alkyl, R″ is a moietysuitable for forming a bond between the compound of Formula III and abiologically-active compound or precursor thereof, and R′″ is a moietysuitable for forming a bond between the compound of Formula IV and abiologically-active compound or precursor thereof.

R″ and R′″ are, independently chosen from carboxylic acid, ester,aldehyde, aldehyde hydrate, acetal, hydroxy, protected hydroxy,carbonate, alkenyl, acrylate, methacrylate, acrylamide, substituted orunsubstituted thiol, halogen, substituted or unsubstituted amine,protected amine, hydrazide, protected hydrazide, succinimidyl,isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties, and can be the same or different from R.

When bound at both ends to a biologically-active compound or precursorthereof, these bifunctional molecules can be represented according toFormula XXIV or Formula XXV:

where each X and Y is independently O, S, CO, CO₂, COS, SO, SO₂, CONR′,SO₂NR′, or NR′, and each R′ and Z is, independently, hydrogen, astraight- or branched-chain, saturated or unsaturated C₁ to C₂₀ alkyl orheteroalkyl group.

Q is a C₃ to C₈ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl (including fused bicyclic and bridged bicyclic ringstructures), a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl or heteroalkaryl group. If present, thesubstituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulfhydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

Each W is, independently, hydrogen or a C₁ to C₇ alkyl, in is zero orone, a is an integer from 4 to 10,000, and each n is independently 0 oran integer from 1 to 5.

R* and R** are independently linking moieties as described above, B andB′ are independently biologically-active molecules and can be the sameor different.

E (through R″ or R″′) can form a bond to another molecule of thebiologically-active compound (B) so that the activated polyalkyleneglycol compound is bound at either terminus to a molecule of the sametype of biologically-active compound, to produce a dimer of themolecule.

In some embodiments, E (through R″ or R′″) forms a bond to abiologically-active compound other than B, creating a heterodimer ofbiologically-active compounds or precursors thereof.

In other embodiments, E (through R″ or R′″) forms an additional bond tothe biologically-active compound, B, such that both E and R are boundthrough different functional groups of the same molecule of thebiologically-active compound or precursor thereof.

R″ and R′″ can be the same as or different from R, and are chosen fromcarboxylic acid, ester, aldehyde, aldehyde hydrate, acetal, hydroxy,protected hydroxy, carbonate, alkenyl, acrylate, methacrylate,acrylamide, substituted or unsubstituted thiol, halogen, substituted orunsubstituted amine, protected amine, hydrazide, protected hydrazide,succinimidyl, isocyanate, isothiocyanate, dithiopyridine, vinylpyridine,iodoacetamide, epoxide, hydroxysuccinimidyl, azole, maleimide, sulfone,allyl, vinylsulfone, tresyl, sulfo-N-succinimidyl, dione, mesyl, tosyl,and glyoxal moieties.

In some embodiments, R* or R** is a methylene group and B or B′ is abiologically-active molecule containing an amino group, where themethylene group forms a bond with the amino group on B. For example, theamine can be the amino terminus of a peptide, an amine of an amino acidside chain of a peptide, or an amine of a glycosylation substituent of aglycosylated peptide. In some embodiments, the peptide is an interferon,such as interferon-beta, e.g., interferon-beta-1a. In some embodiments,this type of bond is formed by a reductive alkylation reaction.

The conjugates of the invention can be prepared by coupling abiologically-active compound to a polyalkylene glycol compound asdescribed in the Examples. In some embodiments, the coupling is achievedvia a reductive alkylation reaction.

Biologically-active compounds of interest include any substance intendedfor diagnosis, cure mitigation, treatment, or prevention of disease inhumans or other animals, or to otherwise enhance physical or mentalwell-being of humans or animals. Examples of biologically-activemolecules include, but are not limited to, peptides, peptide analogs,proteins, enzymes, small molecules, dyes, lipids, nucleosides,oligonucleotides, analogs of oligonucleotides, sugars, oligosaccharides,cells, viruses, liposomes, microparticles, surfaces and micelles. Thisclass of compounds also include precursors of these types of molecules.Classes of biologically-active agents that are suitable for use with theinvention include, but are not limited to, cytokines, chemokines,lymphokines, soluble receptors, antibodies, antibiotics, fungicides,anti-viral agents, anti-inflammatory agents, anti-tumor agents,cardiovascular agents, anti-anxiety agents, hormones, growth factors,steroidal agents, and the like.

The biologically-active compound can be a peptide, such as aninterferon, including interferon-beta (e.g., interferon-beta-1a) orinterferon-alpha.

Because the polymeric modification with a PGC of the invention reducesantigenic responses, a foreign peptide need not be completely autologousin order to be used as a therapeutic. For example, a peptide, such asinterferon, used to prepare polymer conjugates may be prepared from amammalian extract, such as human, ruminant, or bovine interferon, or canbe synthetically or recombinantly produced.

For example, in one aspect, the invention is directed to compounds andmethods for treating conditions that are susceptible of treatment withinterferon alpha or beta. Administration of a polyalkylene glycolconjugated interferon beta (hereinafter “PGC IFN-beta”, “PGC IFN-β”,e.g., PEG IFN-beta”, “PEG IFN-β” “PEGylated IFN-beta”, or “PEGylatedIFN-β”) provides improved therapeutic benefits, while substantiallyreducing or eliminating entirely the undesirable side effects normallyassociated with conventionally practiced interferon alpha or betatreatment regimes.

The PGC IFN-beta can be prepared by attaching a polyalkylene polymer tothe terminal amino group of the IFN beta molecule. A single activatedpolyalkylene glycol molecule can be conjugated to the N-terminus of IFNbeta via a reductive alkylation reaction.

The PGC IFN-beta conjugate can be formulated, for example, as a liquidor a lyophilized powder for injection. The objective of conjugation ofIFN beta with a PGC is to improve the delivery of the protein bysignificantly prolonging its plasma half-life, and thereby provideprotracted activity of IFN beta.

The term “interferon” or “IFN” as used herein means the family of highlyhomologous species-specific proteins that inhibit viral replication andcellular proliferation and modulate immune response. Human interferonsare grouped into two classes; Type 1, including α- and β-interferon, andType II, which is represented by γ-interferon only. Recombinant forms ofeach group have been developed and are commercially available. Subtypesin each group are based on antigenic/structural characteristics.

The terms “beta interferon”, “beta-interferon”, “beta IFN”, “beta-IFN”,“13 interferon”, “β-interferon”, “(β IFN”, “β-IFN”, “interferon beta”,“interferon-beta”, “interferon β”, “interferon-β”, “IFN beta”,“IFN-beta”, “IFN β”, “IFN-β”, and “human fibroblast interferon” are usedinterchangeably herein to describe members of the group of interferonbeta's which have distinct amino acid sequences as have been identifiedby isolating and sequencing DNA encoding the peptides.

Additionally, the terms “beta interferon 1a”, “beta interferon-1a”“beta-interferon 1a”, “beta-interferon-1a”, “beta IFN 1a”, “betaIFN-1a”, “beta-IFN 1a”, “beta-IFN-1a”, “13 interferon 1a”, “βinterferon-1a”, “β-interferon 1a”, “β-interferon-1a”, “β IFN 1a”, “βIFN-1a”, “β-IFN 1a”, “β-IFN-1a”, “interferon beta 1a”, “interferonbeta-1a”, “interferon-beta 1a”, “interferon-beta-1a”, “interferon β1a”,“interferon β-1a”, “interferon-β1a”, “interferon-β-1a”, “IFN beta 1a”,“IFN beta-1a”, “IFN-beta 1a”, “IFN-beta-1a”, “IFN β 1a”, “IFN β-1a”,“IFN-β 1a”, “IFN-β-1a” are used interchangeably herein to describerecombinantly- or synthetically-produced interferon beta that has thenaturally-occurring (wild type) amino acid sequences.

The advent of recombinant DNA technology applied to interferonproduction has permitted several human interferons to be successfullysynthesized, thereby enabling the large-scale fermentation, production,isolation, and purification of various interferons to homogeneity.Recombinantly produced interferon retains some—or most of—its in vitroand in vivo antiviral and immunomodulatory activities. It is alsounderstood that recombinant techniques could also include aglycosylation site for addition of a carbohydrate moiety on therecombinantly-derived polypeptide.

The construction of recombinant DNA plasmids containing sequencesencoding at least part of human fibroblast interferon and the expressionof a polypeptide having immunological or biological activity of humanfibroblast interferon is also contemplated. The construction of hybridbeta-interferon genes containing combinations of different subtypesequences can be accomplished by techniques known to those of skill inthe art.

Typical suitable recombinant beta-interferons which may be used in thepractice of the invention include but are not limited to interferonbeta-1a such as AVONEX® available from Biogen, Inc., Cambridge, Mass.,and interferon-beta-1b such as BETASERON® available from Berlex,Richmond, Calif.

There are many mechanisms by which IFN-induced gene products provideprotective effects against viral infection. Such inhibitory viraleffects occur at different stages of the viral life cycle. See. U.S.Pat. No. 6,030,785. For example, IFN can inhibit uncoating of viralparticles, penetration, and/or fusion caused by viruses.

Conditions that can be treated in accordance with the present inventionare generally those that are susceptible to treatment with interferon.For example, susceptible conditions include those, which would respondpositively or favorably (as these terms are known in the medical arts)to interferon beta-based therapy. For purposes of the invention,conditions that can be treated with interferon beta therapy describedherein include those conditions in which treatment with an interferonbeta shows some efficacy, but in which the negative side effects ofIFN-β treatment outweigh the benefits. Treatment according to themethods of the invention results in substantially reduced or eliminatedside effects as compared to conventional interferon beta treatment. Inaddition, conditions traditionally thought to be refractory to IFN-βtreatment, or those for which it is impractical to treat with amanageable dosage of IFN-β, can be treated in accordance with themethods of the present invention.

The PGC IFN-β compounds of the invention can be used alone or incombination with one or more agents useful for treatment for aparticular condition. At least one pilot study of recombinant interferonbeta-1a for the treatment of chronic hepatitis C has been conducted. Seegenerally Habersetzer et al., Liver 30:437-441 (2000), incorporatedherein by reference. For example, the compounds can be administered incombination with known antiviral agents for treatment of a viralinfection. See Kakumu et al., Gastroenterology 105:507-12 (1993) andPepinsky, et al., J. Pharmacology and Experimental Therapeutics,297:1059-1066 (2001), incorporated herein by reference.

As used herein, the term “antivirals” may include, for example, smallmolecules, peptides, sugars, proteins, virus-derived molecules, proteaseinhibitors, nucleotide analogs and/or nucleoside analogs. A “smallmolecule” as the term is used herein refers to an organic molecule ofless than about 2500 amu (atomic mass units), preferably less than about1000 amu. Examples of suitable antiviral compounds include, but are notlimited to, ribavirin, levovirin, MB6866, zidovudine 3TC, FTC,acyclovir, gancyclovir, viramide, VX-497, VX-950, and ISIS-14803.

Exemplary conditions which can be treated with interferon include, butare not limited to, cell proliferation disorders, in particular multiplesclerosis, cancer (e.g., hairy cell leukemia, Kaposi's sarcoma, chronicmyelogenous leukemia, multiple myeloma, basal cell carcinoma andmalignant melanoma, ovarian cancer, cutaneous T cell lymphoma), andviral infections. Without limitation, treatment with interferon may beused to treat conditions which would benefit from inhibiting thereplication of interferon-sensitive viruses. For example, interferon canbe used alone or in combination with AZT in the treatment of humanimmunodeficiency virus (HIV)/AIDS or in combination with ribavirin inthe treatment of HCV. Viral infections which may be treated inaccordance with the invention include, but are not limited to, hepatitisA, hepatitis B, hepatitis C, other non-Anon-B hepatitis, herpes virus,Epstein-Barr virus (EBV), cytomegalovirus (CMV), herpes simplex, humanherpes virus type 6 (HHV-6), papilloma, poxvirus, picornavirus,adenovirus, rhinovirus, human T lymphotropic virus-type and 2(HTLV-1/-2), human rotavirus, rabies, retroviruses including HIV,encephalitis, and respiratory viral infections. The methods of theinvention can also be used to modify various immune responses.

A correlation between HCV genotype and response to interferon therapyhas been observed. See U.S. Pat. No. 6,030,785; Enomoto et al., N. Engl.J. Med. 334:77-81 (1996); Enomoto et al., J. Clin. Invest. 96:224-30(1995). The response rate in patients infected with HCV-1b is less than40%. See U.S. Pat. No. 6,030,785. Similar low response rates have alsobeen observed in patients infected with HCV-1a. See id.; Hoofnagel etal., Intervirology 37:87-100 (1994). However, the response rate inpatients infected with HCV-2 is nearly 80%. See U.S. Pat. No. 6,030,785;Fried et al., Semin. Liver Dis. 15:82-91 (1995). In fact, an amino acidsequence of a discrete region of the NS5A protein of HCV genotype 1b wasfound to correlate with sensitivity to interferon. See U.S. Pat. No.6,030,785, incorporated herein by reference. See also Enomoto et al.1996; Enomoto et al. 1995. This region has been identified as theinterferon sensitivity determining region (ISDR). See id.

The PGC IFN-beta conjugate is administered in apharmacologically-effective amount to treat any of the conditionsdescribed above, and is based on the IFN beta activity of the polymericconjugate. The term “pharmacologically-effective amount” means theamount of a drug or pharmaceutical agent that will elicit the biologicalor medical response of a tissue, system, animal or human that is beingsought by a researcher or clinician. It is an amount that is sufficientto significantly affect a positive clinical response while maintainingdiminished levels of side effects. The amount of PGC IFN-beta which maybe administered to a subject in need thereof is in the range of 0.01-100μg/kg, or more preferably 0.01-10 μg/kg, administered in single ordivided doses.

Administration of the described dosages may be every other day, butpreferably occurs once a week or once every other week. Doses areadministered over at least a 24 week period by injection.

Administration of the dose can be oral, topical, intravenous,subcutaneous, intramuscular, or any other acceptable systemic method.Based on the judgment of the attending clinician, the amount of drugadministered and the treatment regimen used will, of course, bedependent on the age, sex and medical history of the patient beingtreated, the neutrophil count (e.g., the severity of the neutropenia),the severity of the specific disease condition and the tolerance of thepatient to the treatment as evidenced by local toxicity and by systemicside-effects.

In practice, the conjugates of the invention are administered in amountswhich will be sufficient to inhibit or prevent undesired medicalconditions or disease in a subject, such as a mammal, and are used inthe form most suitable for such purposes. The compositions arepreferably suitable for internal use and include an effective amount ofa pharmacologically-active compound of the invention, alone or incombination with other active agents, with one or morepharmaceutically-acceptable carriers. The compounds are especiallyuseful in that they have very low, if any, toxicity.

The conjugates herein described can form the active ingredient of apharmaceutical composition, and are typically administered in a mixturewith suitable pharmaceutical diluents, excipients or carriers(collectively referred to herein as “carrier” materials) suitablyselected with respect to the intended form of administration, that is,oral tablets, capsules, elixirs, syrups and the like. The compositionstypically will include an effective amount of active compound or thepharmaceutically-acceptable salt thereof, and in addition, and may alsoinclude any carrier materials as are customarily used in thepharmaceutical sciences. Depending on the intended mode ofadministration, the compositions may be in solid, semi-solid or liquiddosage form, such as, for example, injectables, tablets, suppositories,pills, time-release capsules, powders, liquids, suspensions, or thelike, preferably in unit dosages.

Conventional pharmaceutical compositions comprising apharmacologically-effective amount of a conjugate, e.g., PGC IFN-beta,together with pharmaceutically-acceptable carriers, adjuvants, diluents,preservatives and/or solubilizers may be used in the practice of theinvention. Pharmaceutical compositions of interferon include diluents ofvarious buffers (e.g., arginine, Tris-HCl, acetate, phosphate) having arange of pH and ionic strength, carriers (e.g., human serum albumin),solubilizers (e.g., tween, polysorbate), and preservatives (e.g., benzylalcohol). See, for example, U.S. Pat. No. 4,496,537.

Administration of the active compounds described herein can be via anyof the accepted modes of administration for therapeutic agents. Thesemethods include systemic or local administration such as oral, nasal,parenteral, transdermal, subcutaneous, or topical administration modes.

For instance, for oral administration in the form of a tablet or capsule(e.g., a gelatin capsule), the active drug component can be combinedwith an oral, non-toxic pharmaceutically-acceptable inert carrier suchas ethanol, glycerol, water, and the like. Moreover, when desired ornecessary, suitable binders, lubricants, disintegrating agents, andcoloring agents can also be incorporated into the mixture. Suitablebinders include starch, magnesium aluminum silicate, starch paste,gelatin, methylcellulose, sodium carboxymethylcellulose and/orpolyvinylpyrrolidone, sugars, corn sweeteners, natural and syntheticgums such as acacia, tragacanth or sodium alginate, polyethylene glycol,waxes and the like. Lubricants used in these dosage forms include sodiumoleate, sodium stearate, magnesium stearate, sodium benzoate, sodiumacetate, sodium chloride, silica, talcum, stearic acid, its magnesium orcalcium salt, and/or polyethylene glycol and the like. Disintegratorsinclude, without limitation, starch, methyl cellulose, agar, bentonite,xanthan gum starches, agar, alginic acid or its sodium salt, oreffervescent mixtures, and the like. Diluents, include, e.g., lactose,dextrose, sucrose, mannitol, sorbitol, cellulose and/or glycine.

The conjugates of the invention can also be administered in such oraldosage forms as timed-release and sustained-release tablets or capsules,pills, powders, granules, elixers, tinctures, suspensions, syrups, andemulsions.

Liquid, particularly injectable compositions can, for example, beprepared by dissolving, dispersing, etc. The active compound isdissolved in or mixed with a pharmaceutically-pure solvent such as, forexample, water, saline, aqueous dextrose, glycerol, ethanol, and thelike, to thereby form the injectable solution or suspension.Additionally, solid forms suitable for dissolving in liquid prior toinjection can be formulated. Injectable compositions are preferablyaqueous isotonic solutions or suspensions. The compositions may besterilized and/or contain adjuvants, such as preserving, stabilizing,wetting or emulsifying agents, solution promoters, salts for regulatingthe osmotic pressure and/or buffers. In addition, they may also containother therapeutically-valuable substances.

The conjugates of the present invention can be administered inintravenous (e.g., bolus or infusion), intraperitoneal, subcutaneous orintramuscular form, all using forms well known to those of ordinaryskill in the pharmaceutical arts. Injectables can be prepared inconventional forms, either as liquid solutions or suspensions.

Parental injectable administration is generally used for subcutaneous,intramuscular or intravenous injections and infusions. For example, whena subcutaneous injection is used to deliver 0.01-100 μg/kg, or morepreferably 0.01-10 μg/kg of PEGylated IFN-beta over one week, twoinjections of 0.005-50 μg/kg, or more preferably 0.005-5 μg/kg,respectively, may be administered at 0 and 72 hours. Additionally, oneapproach for parenteral administration employs the implantation of aslow-release or sustained-released system, which assures that a constantlevel of dosage is maintained, according to U.S. Pat. No. 3,710,795,incorporated herein by reference.

Furthermore, preferred conjugates for the present invention can beadministered in intranasal form via topical use of suitable intranasalvehicles, or via transdermal routes, using those forms of transdermalskin patches well known to those of ordinary skill in that art. To beadministered in the form of a transdermal delivery system, the dosageadministration will, of course, be continuous rather than intermittentthroughout the dosage regimen. Other preferred topical preparationsinclude creams, ointments, lotions, aerosols, sprays and gels, whereinthe amount administered would be 10-100 times the dose typically givenby parenteral administration.

For solid compositions, excipients include pharmaceutical grades ofmannitol, lactose, starch, magnesium stearate, sodium saccharin, talcum,cellulose, glucose, sucrose, magnesium carbonate, and the like may beused. The active compound defined above, may be also formulated assuppositories using for example, polyalkylene glycols, for example,propylene glycol, as the carrier. In some embodiments, suppositories areadvantageously prepared from fatty emulsions or suspensions.

The conjugates of the present invention can also be administered in theform of liposome delivery systems, such as small unilamellar vesicles,large unilamellar vesicles and multilamellar vesicles. Liposomes can beformed from a variety of phospholipids, containing cholesterol,stearylamine, or phosphatidylcholines. In some embodiments, a film oflipid components is hydrated with an aqueous solution of drug to a formlipid layer encapsulating the drug, as described in U.S. Pat. No.5,262,564.

Conjugates of the present invention may also be delivered by the use ofimmunoglobulin fusions as individual carriers to which the compoundmolecules are coupled. The compounds of the present invention may alsobe coupled with soluble polymers as targetable drug carriers. Suchpolymers can include polyvinylpyrrolidone, pyran copolymer,polyhydroxypropyl-methacrylamide-phenol,polyhydroxyethylaspanamidephenol, or polyethyleneoxidepolylysinesubstituted with palmitoyl residues. The conjugates can also be coupledto proteins, such as, for example, receptor proteins and albumin.Furthermore, the compounds of the present invention may be coupled to aclass of biodegradable polymers useful in achieving controlled releaseof a drug, for example, polylactic acid, polyepsilon caprolactone,polyhydroxy butyric acid, polyorthoesters, polyacetals,polydihydropyrans, polycyanoacrylates and cross-linked or amphipathicblock copolymers of hydrogels.

If desired, the pharmaceutical composition to be administered may alsocontain minor amounts of non-toxic auxiliary substances such as wettingor emulsifying agents, pH buffering agents, and other substances such asfor example, sodium acetate, triethanolamine oleate, etc.

The dosage regimen utilizing the conjugates is selected in accordancewith a variety of factors including type, species, age, weight, sex andmedical condition of the patient; the severity of the condition to betreated; the route of administration; the renal and hepatic function ofthe patient; and the particular compound or salt thereof employed. Theactivity of the compounds of the invention and sensitivity of thepatient to side effects are also considered. An ordinarily skilledphysician or veterinarian can readily determine and prescribe theeffective amount of the drug required to prevent, counter or arrest theprogress of the condition.

Oral dosages of the present invention, when used for the indicatedeffects, will range between about 0.01-100 μg/kg/day orally, or morepreferably 0.01-10 μg/kg/day orally. The compositions are preferablyprovided in the form of scored tablets containing 0.5-5000 μg, or morepreferably 0.5-500 μg of active ingredient.

For any route of administration, divided or single doses may be used.For example, compounds of the present invention may be administereddaily or weekly, in a single dose, or the total dosage may beadministered in divided doses of two, three or four.

Any of the above pharmaceutical compositions may contain 0.1-99%, 1-70%,or, preferably, 1-50% of the active compounds of the invention as activeingredients.

As described above, the course of the disease and its response to drugtreatments may be followed by clinical examination and laboratoryfindings. The effectiveness of the therapy of the invention isdetermined by the extent to which the previously described signs andsymptoms of a condition, e.g., chronic hepatitis, are alleviated and theextent to which the normal side effects of interferon (i.e., flu-likesymptoms such as fever, headache, chills, myalgia, fatigue, etc. andcentral nervous system related symptoms such as depression, paresthesia,impaired concentration, etc.) are eliminated or substantially reduced.

In some embodiments, a polyalkylated compound of the invention (e.g., aPEGylated interferon) is administered in conjunction with one or morepharmaceutical agents useful for treatment for a particular condition.For example, a polyalkylated protein can be administered in combinationwith a known antiviral agent or agent for treatment of a viralinfection. Such antiviral compounds include, for example, ribavirin,levovirin, MB6866, and zidovudine 3TC, FTC, acyclovir, gancyclovir,viramide, VX-497, VX-950, and ISIS-14803.

The conjugate and antiviral can be simultaneously administered (e.g.,the agents are administered to a patient together); sequentiallyadministered (e.g., the agents are administered to the patient one afterthe other); or alternatively administered (e.g., the agents areadministered in a repeating series, such as agent A then agent B, thenagent A, etc.).

In the practice of the invention, the preferred PGC IFN-beta (e.g., PEGIFN-beta) may be administered to patients infected with the hepatitis Cvirus. Use of PEG IFN-beta-1a is preferred.

Patients are selected for treatment from anti-HCV antibody-positivepatients with biopsy-documented chronic active hepatitis.

In order to follow the course of HCV replication in subjects in responseto drug treatment, HCV RNA may be measured in serum samples by, forexample, a nested polymerase chain reaction assay that uses two sets ofprimers derived from the NS3 and NS4 non-structural gene regions of theHCV genome. See Farci et al., 1991, New Eng. J. Med. 325:98-104. Ulrichet al., 1990. J. Clin. Invest., 86:1609-1614.

Antiviral activity may be measured by changes in HCV-RNA titer. HCV RNAdata may be analyzed by comparing titers at the end of treatment with apre-treatment baseline measurement. Reduction in HCV RNA by week 4provides evidence of antiviral activity of a compound. See Meter et al.,1993, Antimicrob. Agents Chemother. 37(3):595-97; Orito et al., 1995, J.Medical Virology, 46:109-115. Changes of at least two orders ofmagnitude (>2 log) is interpreted as evidence of antiviral activity.

A person suffering from chronic hepatitis C infection may exhibit one ormore of the following signs or symptoms: (a) elevated serum alanineaminotransferase (ALT), (b) positive test for anti-HCV antibodies, (c)presence of HCV as demonstrated by a positive test for HCV-RNA, (d)clinical stigmata of chronic liver disease, (e) hepatocellular damage.Such criteria may not only be used to diagnose hepatitis C, but can beused to evaluate a patient's response to drug treatment.

Elevated alanine aminotransferase (ALT) and aspartate aminotransferase(AST) are known to occur in uncontrolled hepatitis C, and a completeresponse to treatment is generally defined as the normalization of theseserum enzymes, particularly ALT. See Davis et al., 1989, New Eng. J.Med. 321:1501-1506. ALT is an enzyme released when liver cells aredestroyed and is symptomatic of HCV infection. Interferon causessynthesis of the enzyme 2′,5′-oligoadenylate synthetase (2′5′OAS), whichin turn, results in the degradation of the viral mRNA. See Houglum,1983, Clinical Pharmacology 2:20-28. Increases in serum levels of the2′5′OAS coincide with decrease in ALT levels.

Histological examination of liver biopsy samples may be used as a secondcriteria for evaluation. See, e.g., Knodell et al., 1981, Hepatology1:431-435, whose Histological Activity

Index (portal inflammation, piecemeal or bridging necrosis, lobularinjury, and fibrosis) provides a scoring method for disease activity.

Safety and tolerability or treatment may be determined by clinicalevaluations and measure of white blood cell and neutrophil counts. Thismay be assessed through periodic monitoring of hematological parameterse.g., white blood cell, neutrophil, platelet, and red blood cellcounts).

Various other extended- or sustained-release formulations can beprepared using conventional methods well known in the art.

Many modifications and variations of this invention can be made withoutdeparting from its spirit and scope, as will be apparent to thoseskilled in the art. The specific embodiments described herein areoffered by way of example only, and the invention is to be limited onlyby the terms of the appended claims, along with the full scope ofequivalents to which such claims are entitled. All patents andpublications cited herein are incorporated by reference.

EXAMPLES Example 1 Synthesis of Activated Polyalkylene Glycols

A) Alkylation of Alcohols

Activated polyalkylene glycols are synthesized by alkylating apolyalkylene glycol having a free terminal hydroxyl functionality. Ageneric reaction is outlined in Scheme I:

The polyalkylene glycol (P—OH) is reacted with the alkyl halide (A) toform the ether (B). Compound B is then hydroxylated to form the alcohol(C), which is oxidized to the aldehyde (D). In these compounds, n is aninteger from zero to five and Z can be a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group. Z canalso be a C₃ to C₇ saturated or unsaturated cyclic alkyl or cyclicheteroalkyl, a substituted or unsubstituted aryl or heteroaryl group, ora substituted or unsubstituted alkaryl (the alkyl is a C₁ to C₂₀saturated or unsaturated alkyl) or heteroalkaryl group. For substitutedcompounds, the substituents can be halogen, hydroxyl, carbonyl,carboxylate, ester, formyl, acyl, thiocarbonyl, thioester, thioacetate,thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate, amino,amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, oralkylthio. Typically, P—OH is polyethylene glycol (PEG) or monomethoxypolyethylene glycol (mPEG) having a molecular weight of 5,000 to 40,000Daltons (Da).

For example, the synthesis of mPEG-O-2-methylpropionaldehyde is outlinedin Scheme II.

mPEG-OH with a molecular weight of 20,000 Da (mPEG-OH 20 kDa; 2.0 g, 0.1mmol, Sunbio) was treated with NaH (12 mg, 0.5 mmol) in THF (35 mL).Fifty equivalents of 3-bromo-2-methylpropene (3.34 g, 5 mmol) and acatalytic amount of KI were then added to the mixture. The resultingmixture was heated to reflux for 16 h. Water (1 mL) was then added andthe solvent was removed under vacuum. To the residue was added CH₂Cl₂(25 mL) and the organic layer was separated, dried over anhydrousNa₂SO₄, and the volume was reduced to approximately 2 mL. ThisCH₂Cl₂solution was added to ether (150 mL) drop-wise. The resultingwhite precipitate was collected, yielding 1.9 g of compound 1. ¹HNMR(CDCl₃, 400 MHz) showed δ 4.98 (s, 1H), 4.91 (s, 1H), 1.74 (s, 3H).

To compound 1 (1.9 g, 0.1 mmol) in THF (20 mL) and CH₂Cl₂ (2 mL) at 0°C., was added BH₃ in THF (1.0 M, 3.5 mL). The mixture was stirred in anice bath for 1 h. To this mixture, NaOH was added slowly (2.0 M, 2.5mL), followed by 30% H₂O₂ (0.8 mL). The reaction was warmed to roomtemperature and stirred for 16 h. The above work-up procedure wasfollowed (CH₂Cl₂, precipitated from ether) to yield 1.8 g of 2 as awhite solid. ¹HNMR (CDCl₃, 400 MHz) showed δ 1.80 (m, 1H), 0.84 (d, 3H).

Compound 2 (250 mg) was dissolved in CH₂Cl₂ (2.5 mL) and Dess-Martinperiodinate (DMP; 15 mg) was added with stirring for 30 min at roomtemperature. To the mixture was added saturated NaHCO₃ and Na₂S₂O₃ (2mL) and the mixture was stirred at room temperature for 1 h. The abovework-up procedure was followed to give 3(mPEG-O-2-methylpropionaldehyde, 120 mg) as a white solid. ¹HNMR (CDCl₃,400 MHz) showed δ 9.75 (s, 1H), 2.69 (m, 1H), 1.16 (d, 3H).

A similar procedure is followed for aromatic alcohols, as shown inScheme III:

In general, the aromatic alcohol (E) is reacted with the alkyl halide(A) to form the mono ether (F). The remaining alcohol group of compoundF is then converted to the halide (e.g., bromide) in Compound G, whichis reacted with the polyalkylene glycol (P—OH) to give the ether (H).This compound is then converted to the aldehyde (J) through ahydroboration to the primary alcohol (I) followed by oxidation. In thesecompounds, n is an integer from zero to five, d is zero or an integerfrom one to four, and Z can be a straight- or branched-chain, saturatedor unsaturated C₁ to C₂₀ alkyl or heteroalkyl group. Z can also be a C₃to C₇ saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl (the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl) or heteroalkaryl group. For substituted compounds,the substituents can be halogen, hydroxyl, carbonyl, carboxylate, ester,formyl, acyl, thiocarbonyl, thioester, thioacetate, thioformate,alkoxyl, phosphoryl, phosphonate, phosphinate, amino, amido, amidine,imine, cyano, nitro, azido, sulthydryl, sulfate, sulfonate, sulfamoyl,sulfonamido, sulfonyl, heterocyclyl, aralkyl, aromatic moiety,heteroaromatic moiety, imino, silyl, ether, or alkylthio.

Additionally, T₁ and T₂ are, independently, absent, or a straight- orbranched-chain, saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkylgroup, and can be ortho, meta, or para to each other. Each L (whenpresent) is, independently, a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₇ saturated orunsaturated cyclic alkyl or cyclic heteroalkyl, a substituted orunsubstituted aryl or heteroaryl group or a substituted or unsubstitutedalkaryl wherein the alkyl is a C₁ to C₂₀ saturated or unsaturated alkylor heteroalkaryl group. The substituents can be halogen, hydroxyl,carbonyl, carboxylate, ester, formyl, acyl, thiocarbonyl, thioester,thioacetate, thioformate, alkoxyl, phosphoryl, phosphonate, phosphinate,amino, amido, amidine, imine, cyano, nitro, azido, sulfhydryl, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, heterocyclyl, aralkyl,aromatic moiety, heteroaromatic moiety, imino, silyl, ether, oralkylthio.

Usually, P—OH is polyethylene glycol (PEG) or monomethoxy polyethyleneglycol (mPEG) having a molecular weight of 5,000 to 40,000 Da.

For example, the synthesis ofmPEG-O-p-methylphenyl-O-2-methylpropionaldehyde (8) is shown in SchemeIV;

To a solution of 4-hydroxybenzylalcohol (2.4 g, 20 mmol) in THF (50 mL)and water (2.5 mL) was first added sodium hydroxide (1.5 g, 37.5 mmol)and then 3-bromo-2-methylpropene (4.1 g, 30 mmol). This reaction mixturewas heated to reflux for 16 h. To the mixture was added 10% citric acid(2.5 mL) and the solvent was removed under vacuum. The residue wasextracted with ethyl acetate (3×15 mL) and the combined organic layerswere washed with saturated NaCl (10 mL), dried and concentrated to givecompound 4. (3.3 g, 93%). ¹HNMR (CDCl₃, 400 MHz) showed δ 7.29 (m, 2H),6.92 (m, 2H), 5.14 (s, 1H), 5.01 (s, 1H), 4.56 (s, 2H), 4.46 (s, 2H),1.85 (s, 3H).

Mesyl chloride (MsCl; 2.5 g, 15.7 mmol) and triethyl amine (TEA; 2.8 mL,20 mmol) were added to a solution of compound 4 (2.0 g, 11.2 mmol) inCH₂Cl₂ (25 mL) at 0° C. and the reaction was placed in the refrigeratorfor 16 h. A usual work-up yielded a pale yellow oil (2.5 g, 87%). ¹HNMR(CDCl₃, 400 MHz) showed δ 7.31 (m, 2H), 6.94 (m, 2H), 5.16 (s, 1H), 5.01(s, 1H), 5.03 (s, 2H), 4.59 (s, 2H), 4.44 (s, 2H), 3.67 (s, 3H), 1.85(s, 3H). This oil (2.4 g, 9.4 mmol) was dissolved in THF (20 mL) andLiBr (2.0 g, 23.0 mmol) was added. The reaction mixture was heated toreflux for 1 h and was then cooled to room temperature. Water (2.5 mL)was added to the mixture and the solvent was removed under vacuum. Theresidue was extracted with ethyl acetate (3×15 mL) and the combinedorganic layers were washed with saturated NaCl (10 mL), dried overanhydrous Na₂SO₄, and concentrated to give the desired bromide 5 (2.3 g,96%) as a pale yellow oil. ¹HNMR (CDCl₃, 400 MHz) showed δ 7.29 (m, 2H),6.88 (m, 2H), 5.11 (s, 1H), 4.98 (s, 1H), 4.53 (s, 2H), 4.44 (s, 2H),1.83 (s, 3H).

mPEG-OH 20 kDa (2.0 g, 0.1 mmol, Sunbio) was treated with NaH (12 mg,0.5 mmol) in THF (35 mL) and compound 5 (0.55 g, 22.8 mmol) was added tothe mixture with a catalytic amount of K1. The resulting mixture washeated to reflux for 16 h. Water (1.0 mL) was added to the mixture andthe solvent was removed under vacuum. To the residue was added CH₂Cl₂(25 mL) and the organic layer was separated, dried over anhydrousNa₂SO₄, and the volume was reduced to approximately 2 mL. Drop-wiseaddition to an ether solution (150 mL) resulted in a white precipitatewhich was collected to yield 6 (1.5 g) as a white powder. ¹HNMR (CDCl₃,400 MHz) showed δ 7.21 (d, 2H), 6.90 (d, 2H), 5.01 (s, 1H), 4.99 (s,1H), 4.54 (s, 2H), 4.43 (s, 2H), 1.84 (s, 3H).

To a solution of compound 6 (1.0 g, 0.05 mmol) in THF (10 mL) and CH₂Cl₂(2 mL) cooled to 0° C., was added BH₃/THF (1.0 M, 3.5 mL) and thereaction was stirred for 1 h. A 2.0 M NaOH solution (2.5 mL) was addedslowly and followed by 30% H₂O₂ (0.8 mL). The reaction mixture wasallowed to warm to room temperature and stirred for 16 h. The abovework-up procedure was followed (CH₂Cl₂, precipitated from ether) toyield 7 (350 mg) as a white solid. ¹HNMR (CDCl₃, 400 MHz) showed δ 7.21(d, 2H), 6.84 (d, 2H), 4.54 (s, 2H), 2.90 (m, 2 H), 1.96 (d, 3H).

Compound 7 (150 mg, 0.0075 mmol) was dissolved in CH₂Cl₂ (1.5 mL) andDMP (15 mg) was added while the reaction mixture was stirred at roomtemperature for 1.5 h. ¹HNMR (CDCl₃, 400 MHz) showed δ 9.76 (s, 1H),7.21 (d, 2H), 6.78 (d, 2H), 4.44 (s, 2H), 4.14 (m, 2H), 2.85 (m, 1H),1.21 (d, 3H). To the mixture was added saturated NaHCO₃ (0.5 mL) andNa₂S₂O₃ (0.5 mL) and stirring continued at room temperature for 1 h. Theabove work-up procedure was followed (CH₂Cl₂ solution, precipitated fromether) to give 8 (92 mg) as a white solid.

Similarly, mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde (9) wassynthesized as outlined in Scheme V.

To a solution of 3-hydroxybenzylalcohol (2.4 g, 20 mmol) in THF (50 mL)and water (2.5 mL) was first added sodium hydroxide (1.5 g, 37.5 mmol)and then 3-bromo-2-methylpropene (4.1 g, 30 mmol). This reaction mixturewas heated to reflux for 16 h. To the mixture was added 10% citric acid(2.5 mL) and the solvent was removed under vacuum. The residue wasextracted with ethyl acetate (3×15 mL) and the combined organic layerswere washed with saturated NaCl (10 mL), dried and concentrated to givecompound 10 (3.2 g, 90%). ¹HNMR (CDCl₃, 400 MHz) showed δ 7.26 (m, 1H),6.94 (m, 2H), 6.86 (m, 1H), 5.11 (s, 1H), 5.01 (s, 1H), 4.61 (s, 1H),4.44 (s, 2H), 1.82 (s, 3H).

MsCl (2.5 g, 15.7 mmol) and TEA (2.8 mL, 20 mmol) were added to asolution of compound 10 (2.0 g, 11.2 mmol) in CH₂Cl₂ (25 mL) at 0° C.and the reaction was placed in the refrigerator for 16 h. A usualwork-up yielded a pale yellow oil (2.5 g, 87%). ¹HNMR (CDCl₃, 400 MHz)showed δ 7.31 (m, 1H), 7.05 (m, 2H), 6.91 (m, 1H), 5.16 (s, 1H), 5.04(s, 1H), 4.59 (s, 1H), 4.46 (s, 2H), 3.71 (s, 3H), 1.84 (s, 3H). Thisoil (2.4 g, 9.4 mmol) was dissolved in THF (20 mL) and LiBr (2.0 g, 23.0mmol) was added. The reaction mixture was heated to reflux for 1 h andwas then cooled to room temperature. To the mixture was added water (2.5mL) and the solvent was removed under vacuum. The residue was extractedwith ethyl acetate (3×15 mL) and the combined organic layers were washedwith saturated NaCl (10 mL), dried over anhydrous Na₂SO₄, andconcentrated to give the desired bromide 11 (2.2 g, 92%) as a paleyellow oil. ¹HNMR (CDCl₃, 400 MHz) showed δ 7.29 (m, 1H), 6.98 (m, 2H),6.85 (m, 1H), 5.14 (s, 2H), 4.98 (s, 2H), 4.50 (s, 2H), 4.44 (s, 2H),1.82 (d, 3H).

mPEG-OH 20 kDa (2.0 g, 0.1 mmol, Sunbio) was treated with NaH (12 mg,0.5 mmol) in THF (35 mL) and compound 11 (0.55 g, 22.8 mmol) was addedto the mixture with a catalytic amount of KI. The resulting mixture washeated to reflux for 16 h. Water (1.0 mL) was added to the mixture andthe solvent was removed under vacuum. To the residue was added CH₂Cl₂(25 mL) and the organic layer was separated, dried over anhydrousNa₂SO₄, and the volume was reduced to approximately 2 mL. Drop-wiseaddition to an ether solution (150 mL) resulted in a white precipitatewhich was collected to yield 12 (1.8 g) as a white powder. ¹HNMR (CDCl₃,400 MHz) showed δ 7.19 (m, 1H), 6.88 (m, 2H), 6.75 (m, 1H), 4.44 (s,2H), 4.10 (m, 2H), 1.82 (d, 3H).

To a solution of compound 12 (1.0 g, 0.05 mmol) in THF (7.5 mL) andCH₂Cl₂ (2.5 mL) cooled to 0° C., was added BH₃THF (1.0 M, 3.5 mL) andthe reaction was stirred for 1 h. A 2.0 M NaOH solution (3 mL) was addedslowly, followed by 30% H₂O₂ (0.85 mL). The reaction mixture was allowedto warm to room temperature and stirred for 16 h. The above work-upprocedure was followed (CH₂Cl₂, precipitated from ether) to yield 13(450 mg) as a white solid. ¹HNMR (CDCl₃, 400 MHz) showed δ 7.15 (m, 1H),6.84 (m, 2H), 6.69 (m, 1H), 4.50 (s, 2H), 2.90 (m, 2 H), 1.95 (d, 3H).

Compound 13 (200 mg, 0.01 mmol) was dissolved in CH₂Cl₂ (1.5 mL) and DMP(20 mg) was added while the reaction mixture was stirred at roomtemperature for 1 h. ¹HNMR (CDCl₃, 400 MHz) showed δ 9.74 (s, 1H), 7.17(m, 1H), 6.86 (m, 2H), 6.74 (m, 1H), 4.48 (s, 2H), 4.15 (m, 2H), 2.78(m, 1H), 1.22 (d, 3H). To the mixture was added saturated NaHCO₃ (0.5mL) and Na₂S₂O₃ (0.5 mL) and stirring continued at room temperature for1 h. The above work-up procedure was followed (CH₂Cl₂ solution,precipitated from ether) to give 9 (142 mg) as a white solid.

B) Generation via Reaction with Aromatic Alcohols

Activated polyalkylene glycols are synthesized by a Mitsunobu reactionbetween a polyalkylene glycol having a free terminal hydroxylfunctionality and an aromatic alcohol. The reaction scheme is outlinedin Scheme VI.

The polyalkylene glycol (P—OH) is reacted with an alcohol (K) to formthe ether (L). In these compounds, m is zero or one, d is zero or aninteger from one to four, and n is zero or an integer from one to five.Y is O, S, CO, CO₂, COS, SO, SO₂, CONR′, SO₂NR′, and NR′. T₁ and T₂ are,independently, absent, or a straight- or branched-chain, saturated orunsaturated C₁ to C₂₀ alkyl or heteroalkyl group.

R′ and Z are, independently, hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group.

Each L (if present) is, independently, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₇saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl. The alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, and the substituents can behalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, aromatic moiety, heteroaromatic moiety, imino,silyl, ether, or alkylthio.

P is a polyalkylene glycol polymer. Usually, P—OH is polyethylene glycol(PEG) or monomethoxy polyethylene glycol (mPEG) having a molecularweight of 5,000 to 40,000 Da.

For example, a synthesis of mPEG-O-p-phenylacetaldehyde (16) is outlinedin Scheme VII.

4-hydroxyphenylacetaldehyde (15) was synthesized as described inHeterocycles, 2000, 53, 777-784. 4-Hydroxyphenethyl alcohol (Compound141.0 g, 7.3 mmol, Aldrich) was dissolved in dimethylsulfoxide (8 mL,Aldrich). With stirring, TEA (2.2 mL, 16 mmol, Aldrich) was addedslowly. Pyridine-sulfur trioxide (SO₃.py) complex (2.5 g, 16 mmol,Aldrich) was completely dissolved in dimethylsulfoxide (9 mL, Aldrich)and this solution was added drop-wise to the alcohol, with vigorousstirring. After stirring for 1 h at room temperature, the reaction wasdiluted with CH₂Cl₂, then washed with ice-cold water. The organic layerwas dried over Na₂SO₄, filtered, and concentrated to dryness.Purification using silica gel chromatography with hexane-ethyl acetateas eluent (5:1, then 2:1) yielded 488 mg (49%) of4-hydroxyphenylacetaldehyde (15).

mPEG-OH 20 kDa (101 mg, 0.005 mmol) and 4-hydroxyphenylacetaldehyde (15)(39 mg, 0.29 mmol) were azeotroped four times with toluene, then takenup in anhydrous CH₂Cl₂ (2 mL, Aldrich). To this solution was addedtriphenylphosphine (PPh₃; 66 mg, 0.25 mmol, Aldrich) and thendiisopropylazodicarboxylate (DIAD; 49 μL, 0.25 mmol, Aldrich) withstirring. After 3 days of stirring at room temperature, the reactionmixture was added drop-wise to vigorously-stirred diethyl ether. Theresulting precipitate was isolated by filtration and washed three timeswith diethyl ether. The crude material was taken up in CH₂Cl₂ and washedwith water. The organic layer was dried over Na₂SO₄, filtered, andconcentrated to dryness. The material was taken up in minimum CH₂Cl₂,then precipitated by adding drop-wise to stirred diethyl ether. Thismaterial was collected by filtration, washed flute times with diethylether and dried to give 63 mg (62%) of mPEG-O-p-phenylacetaldehyde

A synthesis of mPEG-O-p-phenylpropionaldehyde (17) was prepared in asimilar manner.

4-hydroxyphenylpropionaldehyde was prepared by a synthesis analogous tothat for 4-hydroxyphenylacetaldehyde (Heterocycles, 2000, 53, 777-784).3-(4-Hydroxyphenyl)-1-propanol (1.0 g, 6.6 mmol, Aldrich) was dissolvedin dimethylsulfoxide (8 mL, Aldrich). TEA (2.0 mL, 14 mmol, Aldrich) wasadded slowly with stirring. Pyridine-sulfur trioxide (SO₃.py) complex(2.3 g, 15 mmol, Aldrich) was completely dissolved in dimethylsulfoxide(9 mL, Aldrich) and this solution was added drop-wise to the alcohol,with vigorous stirring. After stirring for 1 h at room temperature, thereaction was diluted with CH₂Cl₂, then washed with ice-cold water. Theorganic layer was dried over Na₂SO₄, filtered, and concentrated todryness. Purification using silica gel chromatography with hexane-ethylacetate as eluent (5:1, then 2:1) yielded 745 mg (75%) of4-hydroxyphenylpropionaldehyde.

mPEG-OH 20 kDa (100 mg, 0.005 mmol) and 4-hydroxyphenylpropionaldehyde(40 mg, 0.27 mmol) were azeotroped four times with toluene, then takenup in anhydrous CH₂Cl₂ (2 mL, Aldrich). To this solution was addedtriphenylphosphine (66 mg, 0.25 mmol, Aldrich) and thendiisopropylazodicarboxylate (49 μL, 0.25 mmol, Aldrich) with stirring.After 3 days stirring at room temperature, the reaction mixture wasadded drop-wise to vigorously-stirred diethyl ether. The resultingprecipitate was isolated by filtration and washed three times withdiethyl ether. The crude material was taken up in CH₂Cl₂ and washed withwater. The organic layer was dried over Na₂SO₄, filtered, andconcentrated to dryness. The material was taken up in minimum CH₂Cl₂,then precipitated by adding drop-wise to stirred diethyl ether. Thismaterial was collected by filtration, washed three times with diethylether and dried to give 60 mg (60%) of mPEG-O-p-phenylpropionaldehyde(17).

mPEG-O-m-phenylacetaldehyde (18) was also prepared in this way.

3-hydroxyphenylacetaldehyde was prepared by a synthesis analogous tothat of 4-hydroxyphenylacetaldehyde (Heterocycles, 2000, 53, 777-784).3-Hydroxyphenethyl alcohol (1.0 g, 7.5 mmol, Aldrich) was dissolved indimethylsulfoxide (8 mL, Aldrich). TEA (2.0 mL, 14 mmol, Aldrich) wasadded slowly with stirring. Pyridine-sulfur trioxide (SO₃.py) complex(2.4 g, 15 mmol, Aldrich) was completely dissolved in dimethylsulfoxide(8 mL, Aldrich) and this solution was added drop-wise to the alcohol,with vigorous stirring. After stirring for 1 h at room temperature, thereaction was quenched with ice-cold water, then extracted with CH₂Cl₂.The organic layer was dried over Na₂SO₄, filtered, and concentrated todryness.

Purification using silica gel chromatography with hexane-ethyl acetateas eluent (3:1, then 1:1) yielded 225 mg (22%) of3-hydroxyphenylacetaldehyde.

mPEG-OH 20 kDa (307 mg, 0.015 mmol) and 3-hydroxyphenylacetaldehyde (117mg, 0.86 mmol) were azeotroped four times with toluene, then taken up inanhydrous CH₂Cl₂ (5 mL, Aldrich). To this solution was addedtriphenylphosphine (200 mg, 0.76 mmol, Aldrich) and thendiisopropylazodicarboxylate (147 μL, 0.75 mmol, Aldrich) with stirring.After 3 days of stirring at room temperature, the reaction mixture wasadded drop-wise to vigorously-stirred diethyl ether. The resultingprecipitate was isolated by filtration and washed three times withdiethyl ether and dried to yield 284 mg (93%) ofmPEG-O-m-phenylacetaldehyde (18).

Chiral PEG-cinnamate-N-hydroxy succinimate (NHS) compounds aregenerated, for example, as shown in Schemes VIM and IX:

PEG-Dihydrourocanate-NHS compounds are also generated via a Mitsunobureaction, as shown in Scheme X:

PEG-Dihydrocinnamate-NHS compounds are also generated from an aromaticalcohol as shown in Scheme XI:

PEG-benzofurans and PEG-indoles are generated as shown in Schemes XIIand XIII:

C) Generation via Reaction of PEG-Amines

PEG amines are reacted with alkyl halides to generate PEG-amides. Anexample of the generation of a PEG-amide-bicyclooctane-NHS conjugate isshown in Scheme XIV:

A PEG-primary amine is conjugated with an aryl-halide to form aPEG-secondary amine conjugate, which is then reacted under Heckconditions (a stereospecific Palladium-catalyzed coupling of an alkenewith an organic halide or triflate lacking sp³ hybridized β-hydrogens)with an NHS-alkene to form the desired PEG-conjugate. The synthesis of apyrimidine-containing conjugate is shown in Scheme XV:

PEG-sulfonamide conjugates are also synthesized in this manner, as shownin Scheme XVI:

D) Compounds Generated via Reaction with Heterocycles

PEG compounds are reacted with ring- or non-ring nitrogens inheterocycles to form reactive PEG species. Representative reactions areshown in Schemes XVII for aminopyrrolidine and XVIII for variouspiperazines:

Example 2 Preparation of Peptide Conjugates

The peptide conjugates according to the present invention can beprepared by reacting a protein with an activated PGC molecule. Forexample, interferon (IFN) can be reacted with a PEG-aldehyde in thepresence of a reducing agent (e.g., sodium cyanoborohydride) viareductive alkylation to produce the PEG-protein conjugate, attached viaan amine linkage. See, e.g., European Patent 0154316 B1.

Human IFN-β-1a was PEGylated with the following activated polyalkyleneglycols of the invention: 20 kDa mPEG-O-2-methylpropionaldehyde, 20 kDamPEG-O-p-methylphenyl-0-2-methylpropionaldehyde, 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde, 20 kDamPEG-O-p-phenylacetaldehyde, 20 kDa mPEG-O-p-phenylpropionaldehyde, and20 kDa mPEG-O-m-phenylacetaldehyde. The PEGylated proteins were purifiedto homogeneity from their respective reaction mixtures and subjected toa series of characterization tests to ascertain the identity, purity,and potency of the modified proteins.

A detailed description of the preparation and characterization of humanIFN-β-1a modified with 20 kDa mPEG-O-2-methylpropionaldehyde, 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde, and 20 kDamPEG-O-p-phenylacetaldehyde follows.

A) Preparation and Characterization of 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a

Human IFN-β-1a was PEGylated at its N-terminus with 20 kDamPEG-O-2-methylpropionaldehyde. The product of the reductive alkylationchemistry used to incorporate the PEG onto the IFN-β-1a backboneresulted in the formation of an amine linkage which is extremely stableagainst degradation. The PEGylated IFN-β-1a was subjected to extensivecharacterization, including analysis by SDS-PAGE, size exclusionchromatography (SEC), peptide mapping, and assessment of activity in anin vitro antiviral assay. The purity of the product, as measured bySDS-PAGE and SEC, was greater than 90%. In the PEGylated sample therewas no evidence of aggregates. Residual levels of unmodified IFN-β-1a inthe product were below the limit of quantitation, but appear torepresent about 1% of the product. The specific activity of thePEGylated IFN-β-1a in the antiviral activity assay was reducedapproximately 2-fold compared to the unmodified IFN-β-Ia (EC₅₀=32 pg/mLfor 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a versusEC₅₀=14 pg/mL for unmodified IFN-β-1a). The PEGylated IFN-β-1a bulk wasformulated at 30 μg/mL in phosphate-buffered saline (PBS) pH 7.3,containing 14 mg/mL human serum albumin (HSA), similar to theformulation used for AVONEX® (Biogen, Cambridge, Mass.) which has beensubjected to extensive characterization. The material was supplied as afrozen liquid which was stored at −70° C.

The properties of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a are summarized in Table 1:

TABLE 1 Properties of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a Pegylation efficiency >90% IFN-β-1a/PEG ratio 1:1 Purity >90%Site of attachment N-terminus Antiviral activity EC₅₀ 32 pg/mL

1. Preparation of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a. 10 mL of nonformulated AVONEX® (IFN-β-1a bulk intermediate, aclinical batch of bulk drug that passed all tests for use in humans, at250 μg/mL in 100 mM sodium phosphate pH 7.2, 200 mM NaCl) was dilutedwith 12 mL of 165 mM MES pH 5.0 and 50 μL of 5 N HCl. The sample wasloaded onto a 300 μL SP-Sepharose FF column (Pharmacia). The column waswashed with 3×300 μl, of 5 mM sodium phosphate pH 5.5, 75 mM NaCl, andthe protein was eluted with 5 mM sodium phosphate pH 5.5, 600 mM NaCl.Elution fractions were analyzed for their absorbance at 280 nm and theconcentration of IFN-β-1a in the samples estimated using an extinctioncoefficient of 1.51 for a 1 mg/mL solution. The peak fractions werepooled to give an IFN-β-1a concentration of 3.66 mg/mL, which wassubsequently diluted to 1.2 mg/mL with water.

To 0.8 mL of the IFN-β-1a from the diluted SP-Sepharose eluate pool, 0.5M sodium phosphate pH 6.0 was added to 50 mM, sodium cyanoborohydride(Aldrich) was added to 5 mM, and 20 kDa mPEG-O-2-methylpropionaldehydewas added to 5 mg/mL. The sample was incubated at room temperature for16 h in the dark. The PEGylated IFN-β-1a was purified from the reactionmixture on a 0.5 mL SP-Sepharose FF column as follows: 0.6 mL of thereaction mixture was diluted with 2.4 mL 20 mM MES pH 5.0, and loaded onto the SP-Sepharose column. The column was washed with sodium phosphatepH 5.5, 75 mM NaCl and then the PEGylated IFN-β-1a was eluted from thecolumn with 25 mM MES pH 6.4, 400 mM NaCl. The PEGylated IFN-β-1′-1a wasfurther purified on a Superose 6 HR 10/30 FPLC sizing column with 5 mMsodium phosphate pH 5.5, 150 mM NaCl as the mobile phase. The sizingcolumn (25 mL) was run at 20 mL/h and 0.5 mL fractions were collected.The elution fractions were analyzed for protein content by absorbance at280 nm, pooled, and the protein concentration of the pool determined.The PEGylated IFN-β-1a concentration is reported in IFN equivalents asthe PEG moiety does not contribute to absorbance at 280 nm. Samples ofthe pool were removed for analysis, and the remainder was diluted to 30μg/mL with HSA-containing formulation buffer, aliquoted at 0.25 mL/vial,and stored at −70° C.

2. UV spectrum of purified 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a. The UV spectrum(240-340 nm) of 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1awas obtained using the pre-HSA-formulated bulk sample. The PEGylatedsample exhibited an absorbance maximum at 278-279 nm and an absorbanceminimum at 249-250 nm, consistent with that observed for the unmodifiedIFN-β-1a bulk intermediate. The protein concentration of the PEGylatedproduct was estimated from the spectrum using an extinction coefficientof ε₂₈₀ ^(01%)=1.51. The protein concentration of the PEGylated bulk was0.23 mg/mL. No turbidity was present in the sample as evident by a lackof absorbance at 320 nm.

3. Characterization of 20 kDa mPEG-O-2-methylpropionaldehyde-modified bySDS-PAGE. 4 μg of unmodified and 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a were subjected toSDS-PAGE under reducing conditions on a 10-20% gradient gel. The gel wasstained with Coomassie brilliant blue R-250, and is shown in FIG. 1(Lane A, molecular weight markers (from top to bottom; 100 kDa, 68 kDa,45 kDa, 27 kDa, and 18 kDa, respectively); Lane B, unmodified IFN-β-1a;Lane C, 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a).SDS-PAGE analysis of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a revealed a single major band with an apparent mass of 55 kDa,consistent with modification by a single PEG. No higher mass formsresulting from the presence of additional PEG groups were detected. Inthe purified, PEGylated product, unmodified IFN-β-1a was detected;however, the amount is below the limit of quantitation. The level ofunmodified IFN-β-1a in the preparation is estimated to account for onlyabout 1% of the total protein.

4. Characterization of 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a by size exclusion chromatography. Unmodified and 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a were subjected to SECon an analytical Superose 6 HR10/30 FPLC sizing column using PBS pH 7.2as the mobile phase. The column was run at 20 mL/h and the eluentmonitored for absorbance at 280 nm, as, shown in FIG. 2: Panel A:molecular weight standards (670 kDa, thyroglobulin; 158 kDa, gammaglobulin; 44 kDa, ovalbumin; 17 kDa, myoglobin; 1.3 kDa, vitamin B12),Panel B: 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a; PanelC: unmodified IFN-β-1a. The 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a eluted as a singlesharp peak with an apparent molecular mass of approximately 200 kDa,consistent with the large hydrodynamic volume of the PEG. No evidence ofaggregates was observed. Unmodified IFN-β-1a in the preparation wasdetected but was below the limit of quantitation. Based on the size ofthe peak, the unmodified IFN-β-1a accounts for 1% or less of theproduct, consistent with that observed using SDS-PAGE.

5. Analysis of 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-B-1aby peptide mapping. The specificity of the PEGylation reaction wasevaluated by peptide mapping. Unmodified and 20% DamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a were digested withendoproteinase Lys-C from Achromobacter (Wako Bioproducts) and theresulting cleavage products were fractionated by reverse-phase HPLC on aVydac C₄ column using a 30 min gradient from 0 to 70% acetonitrile, in0.1% TFA. The column eluent was monitored for absorbance at 214 nm.

All of the predicted peptides from the endoproteinase Lys-C digest ofIFN-β-1a have been identified previously by N-terminal sequencing andmass spectrometry (Pepinsky et al., (2001) J Pharmacology andExperimental Therapeutics 297:1059), and, of these, only the peptidethat contains the N-terminus of IFN-β-1a was altered by modificationwith 20 kDa mPEG-O-2-methylpropionaldehyde; as evident by itsdisappearance from the peptide map. The mapping data therefore indicatethat the PEG moiety is specifically attached to this peptide. The datafurther indicate that the PEG modification is targeted at the N-terminusof the protein since only the N-terminal modification would result inthe specific loss of this peptide.

B) Preparation and Characterization of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a

Human IFN-β-1a was PEGylated at the N-terminus with 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde. The product of thereductive alkylation chemistry that was used to incorporate the PEG ontothe IFN-β-1a backbone results in the formation of an amine linkage whichis extremely stable against degradation. The PEGylated IFN-β-1a wassubjected to extensive characterization, including analysis by SDS-PAGE,SEC, peptide mapping, and assessment of activity in an in vitroantiviral assay. The purity of the product as measured by SDS-PAGE andSEC was greater than 95%. In the PEGylated IFN-β-1a sample there was noevidence of aggregates. Residual levels of unmodified IFN-β-1a in theproduct were below the limit of quantitation, but appear to representabout 1% of the product. The specific activity of the PEGylated IFN-β-1ain the antiviral activity assay was reduced approximately 2-foldcompared to the unmodified IFN-β-1a (EC₅₀=31 pg/mL for 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a versusEC₅₀=14 pg/mL for unmodified IFN-β-1a). The PEGylated IFN-β-1a bulk wasformulated at 30 μg/mL in PBS pH 7.2 containing 15 mg/mL HSA, similar tothe formulation used for AVONEX® which has been subjected to extensivecharacterization. The material was supplied as a frozen liquid which wasstored at −70° C.

The properties of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a aresummarized in Table 2:

TABLE 2 Properties of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde- modified IFN-β-1aPEGylation efficiency >80% IFN-β-1a/PEG ratio 1:1 Purity >95% Site ofattachment N-terminus Antiviral activity EC₅₀ 31 pg/mL

1. Preparation of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a. 80 mLof nonformulated AVONEX® (IFN-(3-1a bulk intermediate, a clinical batchof bulk drug that passed all tests for use in humans, at 254 μg/mL in100 mM sodium phosphate pH 7.2, 200 mM NaCl) was diluted with 96 mL of165 mM MES pH 5.0, and 400 μl, of 5 N HCl. The sample was loaded onto a12 mL SP-Sepharose FF column (Pharmacia). The column was washed with 6.5mL of 5 mM sodium phosphate pH 5.5, 75 mM NaCl, and the protein waseluted with 5 mM sodium phosphate pH 5.5, 600 mM NaCl. Elution fractionswere analyzed for their absorbance at 280 nm and the concentration ofIFN-β-1a in the samples was estimated using an extinction coefficient of1.51 for a 1 mg/mL solution. The peak fractions were pooled to give anIFN-β-1a concentration of 4.4 mg/mL. To 2.36 mL of the 4.4 mg/mLIFN-β-1a from the SP-Sepharose eluate pool, 0.5 M sodium phosphate pH6.0 was added to 50 mM, sodium cyanoborohydride (Aldrich) was added to 5mM, and 20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde, wasadded to 10 mg/mL. The sample was incubated at room temperature for 21 hin the dark. The PEGylated IFN-β-1a was purified from the reactionmixture on a 8.0 mL SP-Sepharose FF column as follows: 9.44 ml, ofreaction mixture was diluted with 37.7 mL of 20 mM MES pH 5.0, andloaded onto the SP-Sepharose column. The column was washed with sodiumphosphate pH 5.5, 75 mM NaCl and then the PEGylated IFN-β-1a was elutedfrom the column with 25 mM MES pH 6.4, 400 mM NaCl. The PEGylatedIFN-β-1a was further purified on a Superose 6 HR 10/30 FPLC sizingcolumn with 5 mM sodium phosphate pH 5.5, 150 mM NaCl as the mobilephase. The sizing column (25 mL) was run at 24 mL/h and 0.25 mLfractions were collected. The elution fractions were analyzed forprotein content by SDS-PAGE, pooled, and the protein concentration ofthe pool determined. The PEGylated IFN-β-1a concentration is reported inIFN equivalents after adjusting for the contribution of the PEG to theabsorbance at 280 nm using an extinction coefficient of 2 for a 1 mg/mLsolution of the PEGylated IFN-β-1a. Samples of the pool were removed foranalysis, and the remainder was diluted to 30 μg/mL with HSA-containingformulation buffer, aliquoted at 0.25 mL/vial, and stored at −70° C.

2. UV spectrum of purified 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a. TheUV spectrum (240-340 nm) of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a wasobtained using the pre-HSA-formulated bulk sample. The PEGylated sampleexhibited an absorbance maximum at 278-279 nm and an absorbance minimumat 249-250 nm, consistent with that observed for the unmodified bulkintermediate. The protein concentration of the PEGylated product wasestimated from the spectrum using an extinction coefficient of ε₂₈₀^(0.1%)=2.0. The protein concentration of the PEGylated bulk was 0.42mg/mL. No turbidity was present in the sample as evident by the lack ofabsorbance at 320 nm.

3. Characterization of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a bySDS-PAGE. 2.1 μg of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a wassubjected to SDS-PAGE under reducing conditions on a 4-20% gradient gel.The gel was stained with Coomassie brilliant blue R-250. SDS-PAGEanalysis of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1arevealed a single major band with an apparent mass of 55 kDa consistentwith modification by a single PEG. In the purified PEGylated productunmodified IFN-β-1a was detected; however, the amount is below the limitof quantitation. It is estimated that the level of unmodified IFN-β-1ain the preparation accounts for only about 1% of the total protein.

4. Characterization of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a bysize exclusion chromatography. 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a wassubjected to SEC on an analytical Superose 6 HR10/30 FPLC sizing columnusing PBS pH 7.0 as the mobile phase. The column was run at 24 mL/h andthe eluent was monitored for absorbance at 280 nm. The PEGylatedIFN-β-1a eluted as a single sharp peak with no evidence of aggregates(FIG. 3).

5. Analysis of 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a bypeptide mapping. The specificity of the PEGylation reaction wasevaluated by peptide mapping. 13.3 μg of unmodified and 20 kDamPEG-O-m-methylphenyl-β-2-methylpropionaldehyde-modified IFN-β-1a weredigested with 20% (w/w) of endoproteinase Lys-C from Achromobacter (WakoBioproducts) in PBS containing 5 mM DTT, 1 mM EDTA, at pH 7.6, at roomtemperature for 30 h (final volume=100 μL). 4 μL of 1 M DTT and 100 μLof 8 M urea were then added and the samples incubated for 1 h at roomtemperature. The peptides were separated by reverse-phase HPLC on aVydac C₁₈ column (214TP51) using a 70 mM gradient from 0-63%acetonitrile, in 0.1% TFA, followed by a 10 min gradient from 63-80%acetonitrile, in 0.1% TFA. The column eluent was monitored forabsorbance at 214 nm.

All of the predicted peptides from the endoproteinase Lys-C digest ofIFN-β-1a have been identified previously by N-terminal sequencing andmass spectrometry (Pepinsky et al., (2001) J Pharmacology andExperimental Therapeutics 297:1059), and, of these, only the peptidethat contains the N-terminus of IFN-β-1a was altered by modificationwith 20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde; as evidentby its disappearance from the map. The mapping data therefore indicatethat the PEG moiety is specifically attached to this peptide. The datafurther indicate that the PEG modification is targeted at the N-terminusof the protein since only the N-terminal modification would result inthe specific loss of this peptide.

C) Preparation and Characterization of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a

Human IFN-β-1a was PEGylated at the N-terminus with 20 kDamPEG-O-p-phenylacetaldehyde. The product of the reductive alkylationchemistry that was used to incorporate the PEG onto the IFN-β-1abackbone results in the formation of an amine linkage which is extremelystable against degradation. The PEGylated IFN-β-1a was subjected toextensive characterization, including analysis by SDS-PAGE, SEC, peptidemapping, and assessment of activity in an in vitro antiviral assay. Thepurity of the product as measured by SDS-PAGE and SEC was greater than95%. In the PEGylated IFN-β-1a sample there was no evidence ofaggregates. Residual levels of unmodified IFN-β-1a in the product werebelow the limit of quantitation, but appear to represent about 1% of theproduct. In a stability test, no aggregation or degradation of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a was evident in Tris-bufferpH 7.4, following an incubation at 37° C. for up to 7 days. The specificactivity of the PEGylated IFN-β-1a in the antiviral activity assay wasreduced approximately 2-fold compared to the unmodified IFN-β-1a(EC₅₀₌₃₁ pg/mL for 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1aversus EC₅₀₌₁₄ pg/mL for unmodified IFN-β-1a) The PEGylated IFN-β-1abulk was formulated at 30 μg/mL in PBS pH 7.3 containing 14 mg/mL HSA,similar to the formulation used for AVONEX® which has been subjected toextensive characterization. The material was supplied as a frozen liquidwhich was stored at −70° C.

The properties of 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1aare summarized in Table 3:

TABLE 3 Properties of 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a Pegylation efficiency >80% IFN-β-1a/PEG ratio 1:1 Purity >95%Site of attachment N-terminus Antiviral activity EC₅₀ 31 pg/mL

1. Preparation of 20 kDa mPEG-O-p-phenylacetaldehyde-modified 20 mL ofnonformulated AVONEX® (IFN-β-1a bulk intermediate, a clinical batch ofbulk drug that passed all tests for use in humans, at 250 μg/mL in 100mM sodium phosphate pH 7.2, 200 mM NaCl) was diluted with 24 mL of 165mM MES pH 5.0, 100 μl of 5 N HCl, and 24 mL water. The sample was loadedonto a 600 μL SP-Sepharose FF column (Pharmacia). The column was washedwith 2×900 μL of 5 mM sodium phosphate pH 5.5, 75 mM NaCl, and theprotein was eluted with 5 mM sodium phosphate pH 5.5, 600 mM NaCl.Elution fractions were analyzed for their absorbance at 280 nm and theconcentration of IFN-β-1a in the samples was estimated using anextinction coefficient of 1.51 for a 1 mg/mL solution. The peakfractions were pooled to give an IFN-β-1a concentration of 2.3 mg/mL. To1.2 mL of the IFN-β-1a from the SP-Sepharose eluate pool, 0.5 M sodiumphosphate pH 6.0 was added to 50 mM, sodium cyanoborohydride (Aldrich)was added to 5 mM, and 20 kDa mPEG-O-p-phenylacetaldehyde, was added to10 mg/mL. The sample was incubated at room temperature for 18 h in thedark. The PEGylated IFN-β-1a was purified from the reaction mixture on a0.75 mL SP-Sepharose FF column as follows: 1.5 mL of reaction mixturewas diluted with 7.5 mL of 20 mM MES pH 5.0, 7.5 mL water, and 5 μL 5 NHCl, and loaded onto the SP-Sepharose column. The column was washed withsodium phosphate pH 5.5, 75 mM NaCl and then the PEGylated IFN-β-1a waseluted from the column with 20 mM MES pH 6.0, 600 mM NaCl. The PEGylatedIFN-β-1a was further purified on a Superose 6 HR 10/30 FPLC sizingcolumn with 5 mM sodium phosphate pH 5.5, 150 mM NaCl as the mobilephase. The sizing column (25 mL) was run at 20 mL/h and 0.5 mL fractionswere collected. The elution fractions were analyzed for protein contentby absorbance at 280 nm, pooled, and the protein concentration of thepool determined. The PEGylated IFN-β-1a concentration is reported in IFNequivalents after adjusting for the contribution of the PEG (20 kDamPEG-O-p-phenylacetaldehyde has an extinction coefficient at 280 nm of0.5 for a 1 mg/mL solution) to the absorbance at 280 nm using anextinction coefficient of 2 for a 1 mg/mL solution of the PEGylatedIFN-β-1a. Samples of the pool were removed for analysis, and theremainder was diluted to 30 μg/mL with HSA-containing formulationbuffer, aliquoted at 0.25 mL/vial, and stored at −70° C.

2. UV spectrum of purified 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a. The UV spectrum (240-340 nm) of 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a was obtained using thepre-HSA-formulated bulk sample. The PEGylated sample exhibited anabsorbance maximum at 278-279 nm and an absorbance minimum at 249-250nm, consistent with that observed for the unmodified IFN-β-1a bulkintermediate. The protein concentration of the PEGylated product wasestimated from the spectrum using an extinction coefficient of ε₂₈₀^(0.1)=2.0. The protein concentration of the PEGylated bulk was 0.10mg/mL. No turbidity was present in the sample as evident by the lack ofabsorbance at 320 nm.

3. Characterization of 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a by SDS-PAGE. 2.5 μg of unmodified and 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a were subjected to SDS-PAGEunder reducing conditions on a 10-20% gradient gel. The gel was stainedwith Coomassie brilliant blue R-250, and is shown in FIG. 4 (Lane A: 20kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a; Lane B: unmodifiedIFN-β-1a; Lane C: molecular weight markers (from top to bottom; 100 kDa,68 kDa, 45 kDa, 27 kDa, and 18 kDa, respectively)). SDS-PAGE analysis of20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a revealed a singlemajor band with an apparent mass of 55 kDa consistent with modificationby a single PEG. No higher mass forms resulting from the presence ofadditional PEG groups were detected. In the purified PEGylated productunmodified IFN-β-1a was detected; however, the amount is below the limitof quantitation. It is estimated that the level of unmodified IFN-β-1ain the preparation accounts for only about 1% of the total protein.

4. Characterization of 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a by size exclusion chromatography. 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a was subjected to SEC on ananalytical Superose 6 HR10/30 FPLC sizing column using PBS pH 7.2 as themobile phase. The column was run at 20 mL/h and the eluent was monitoredfor absorbance at 280 nm, as shown in FIG. 5: Panel A: molecular weightstandards (670 kDa, thyroglobulin; 158 kDa, gamma globulin; 44 kDa,ovalbumin; 17 kDa, myoglobin; 1.3 kDa, vitamin B12); Panel B: 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a. The PEGylated IFN-β-1aeluted as a single sharp peak with an apparent molecular mass ofapproximately 200 kDa consistent with the large hydrodynamic volume ofthe PEG. No evidence of aggregates was observed. Unmodified IFN-β-1a inthe preparation was detected but was below the limit of quantitation.Based on the size of the peak, the unmodified IFN-β-1a accounts for 1%or less of the product, consistent with that observed using SDS-PAGE.

5. Analysis of 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a bypeptide mapping. The specificity of the PEGylation reaction wasevaluated by peptide mapping. Unmodified and 20 kDamPEG-O-p-phenylacetaldehyde-modified IFN-β-1a were digested withendoproteinase Lys-C from Achromobacter (Wako Bioproducts) and theresulting cleavage products were fractionated by reverse-phase HPLC on aVydac C₄ column using a 30 min gradient from 0 to 70% acetonitrile, in0.1% TFA. The column eluent was monitored for absorbance at 214 nm.

All of the predicted peptides from the endoproteinase Lys-C digest ofIFN-β-1a have been identified previously by N-terminal sequencing andmass spectrometry (Pepinsky et al., (2001) J Pharmacology andExperimental Therapeutics 297:1059), and, of these, only the peptidethat contains the N-terminus of IFN-β-1a was altered by modificationwith 20 kDa mPEG-O-p-phenylacetaldehyde; as evident by its disappearancefrom the map. The mapping data therefore indicate that the PEG moiety isspecifically attached to this peptide. The data further indicate thatthe PEG modification is targeted at the N-terminus of the protein sinceonly the N-terminal modification would result in the specific loss ofthis peptide.

6. Stability of 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a. Totest the stability of 20 kDa mPEG-O-p-phenylacetaldehyde-modifiedIFN-β-1a, samples were diluted to 0.1 μg/mL with 100 mM Tris-HCl buffer,pH 7.4, and were then incubated at 37° C. for up to 7 days. 20 μL ofsample (2 μg) was removed at days 0, 2, 5, and 7, and analyzed bySDS-PAGE under reducing conditions, as shown in FIG. 6: Lane A:molecular weight markers (from top to bottom; 100 kDa, 68 kDa, 45 kDa,27 kDa, 18 kDa, and 15 kDa, respectively); Lanes B, C, D, and E:mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a removed at day 0, 2, 5,and 7, respectively. No evidence of aggregation or degradation ofPEGylated was observed even after 7 days at 37° C.

Example 3 Specific Activity of PEGylated Human IFN-β-1a in an In vitroAntiviral Assay

The specific antiviral activity of PEGylated IFN-β-1a samples was testedon human lung carcinoma cells (A549 cells) that had been exposed toencephalomyocarditis (EMC) virus, and using the metabolic dye2,3-bis[2-Methoxy-4-nitro-5-sulfo-phenyl]-2H-tetrazolium-5-carboxyanilide(MTT; M-5655, Sigma, Si Louis, Mo.) as a measure of metabolically-activecells remaining after exposure to the virus. Briefly, A549 cells werepretreated for 24 h with either unmodified or PEGylated IFN-β-1a(starting at 66.7 pg/mL and diluting serially 1.5-fold to 0.8 pg/mL)prior to challenge with virus. The cells were then challenged for 2 dayswith EMC virus at a dilution that resulted in complete cell killing inthe absence of IFN. Plates were then developed with MTT. A stocksolution of MTT was prepared at 5 mg/mL in PBS and sterile-filtered, and50 μL of this solution was diluted into cell cultures (100 μL per well).Following incubation at room temperature for 30-60 min, the MTT/mediasolution was discarded, cells were washed with 100 μL PBS, and finallythe metabolized dye was solubilized with 100 μL 1.2 N HCl inisopropanol. Viable cells (as determined by the presence of the dye)were quantified by absorbance at 450 nm. Data were analyzed by plottingabsorbance against the concentration of IFN-β-1a, and the activity ofIFN-β-1a was defined as the concentration at which 50% of the cells werekilled i.e., the 50% cytopathic effect (EC₅₀) or 50% maximum OD₄₅₀. Theassay was performed eight times for unmodified IFN-β-1a and three tofour times with the various PEGylated IFN-β-1a samples. For each assay,duplicate data points for each protein concentration were obtained.Representative plots of cell viability versus the concentration ofunmodified or PEGylated IFN-β-1a are shown in FIGS. 7A and 7B. In FIG.7A, the symbols are as follows: unmodified IFN-β-1a (∘), 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a (□), 20 kDamPEG-O-p-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a (Δ),and 20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified (⋄).In FIG. 7B, the symbols are as follows: unmodified IFN-β-1a (∘), 20 kDamPFG-O-p-phenylacetaldehyde-modified (□), 20 kDamPEG-O-p-phenylpropionaldehyde-modified IFN-β-1a (Δ), and 20 kDamPEG-O-m-phenylacetaldehyde-modified IFN-β-1a (⋄).

The EC₅₀ values (the concentration at half-maximal viral protection) forIFN-β-1a modified with 20 kDa mPEG-O-2-methylpropionaldehyde, 20 kDamPEG-O-p-methylphenyl-O-2-methylpropionaldehyde, 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde, 20 kDamPEG-O-p-phenylacetaldehyde, 20 kDa mPEG-O-p-phenylpropionaldehyde, and20 kDa mPEG-O-m-phenylacetaldehyde are shown in Table 4. All PEGylatedIFN-β-1a were modified and purified to homogeneity essentially asdescribed for 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a,20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modifiedIFN-β-1a, and 20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a asdescribed above.

TABLE 4 Specific antiviral activity of unmodified and PEGylatedIFNs-β-1a Mean EC₅₀ Protein (pg/mL) Unmodified IFN-β-1a 14 (range 12-16)20 kDa mPEG-O-2-methylpropionaldehyde-modified 32 (range 26-37) IFN-β-1a20 kDa mPEG-O-p-methylphenyl-O-2- 41 (range 36-47)methylpropionaldehyde-modified IFN-β-1a 20 kDamPEG-O-m-methylphenyl-O-2- 31 (range 27-35)methylpropionaldehyde-modified IFN-β-1a 20 kDamPEG-O-p-phenylacetaldehyde-modified 31 (range 25-39) IFN-β-1a 20 kDamPEG-O-p-phenylpropionaldehyde-modified 31 (range 27-34) IFN-β-1a 20 kDamPEG-O-m-phenylacetaldehyde-modified 27 (range 25-29) IFN-β-1a

Example 4 Pharmacokinetics of Intravenously-administered Unmodified andPEGylated IFNs-β-1a in Rats

Cannulated female Lewis rats were injected intravenously with either 80μg/kg of unmodified IFN-β-1a or 24 μg/kg of the following PEGylatedIFNs-β-1a; 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a, 20kDa mPEG-O-p-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a,20 kDa mPEG-O-p-phenylacetaldehyde-modified IFN-β-1a, 20 kDamPEG-O-p-phenylpropionaldehyde-modified IFN-β-1a, 20 kDamPEG-β-m-phenylacetaldehyde-modified IFN-β-1a, and 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde-modified IFN-β-1a. Boththe unmodified and PEGylated proteins were formulated in the presence of14-15 mg/mL HSA as a carrier. For the unmodified protein, blood (0.2 mL)was obtained via the cannula at different time points; immediately priorto administration, and at 0.083, 0.25, 0.5, 1.25, 3, and 5 hourspost-administration. For the PEGylated proteins, blood (0.2 mL) wasobtained via the cannula immediately prior to administration, and at0.083, 0.25, 0.5, 1.25, 3, 24, 48, and 72 h post-administration. Wholeblood was collected into serum separator tubes (Beckton Dickinson No.365956) and incubated at room temperature for 60 min to allow forclotting. The clotted blood was centrifuged for 10 min at 4° C., and theserum removed and stored at −70° C. until the time of assay.

The serum samples were then thawed and tested in antiviral assays. Theserum samples were diluted 1:50 into serum-containing medium (Dulbecco'sModified Eagles Medium containing 10% (v/v) fetal bovine serum, 100 Ueach of penicillin and streptomycin, and 2 mM

L-glutamine) and tested in antiviral assays. Samples were titrated intodesignated wells of a 96 well tissue culture plate containing human lungcarcinoma cells (A549, #CCL-185, ATCC, Rockville, Md.). Dilutions of astandard (66.7, 44.4, 29.6, 19.8, 13.2, 8.8, 5.9, 3.9, 2.6, 1.7, 1.2,and 0.8 pg/mL of the same form of IFN-β-1a administered to the rat) andof three serum samples were assayed on each plate. The A549 cells werepretreated with diluted serum samples for 24 h prior to challenge withencephalomyelocarditis (EMC) virus. Following a 2 day incubation withvirus, viable cells were stained with a solution of MTT (at 5 mg/mL inphosphate buffer) for 1 h, washed with phosphate buffer, and solubilizedwith 1.2 N HCl in isopropanol. The wells were then read at 450 nm.Standard curves of the unmodified or PEGylated IFN-β-1a were generatedfor each plate and used to determine the amount of unmodified orPEGylated IFN-β-1a in each test sample. Pharmacokinetic parameters werethen calculated using non-compartmental analysis with WinNonLin version3.0 or 3.3 software.

FIG. 8A shows the concentration versus time plots for unmodifiedIFN-β-1a (upper panel) and IFN-β-1a modified with 20 kDamPEG-O-2-methylpropionaldehyde (lower panel), and FIG. 8B shows theconcentration versus time plots for IFN-β-1a modified with 20 kDamPEG-O-p-methylphenyl-O-2-methylpropionaldehyde (upper panel) and 20 kDamPEG-O-p-phenylacetaldehyde (lower panel). Data points are averages frommeasurements from 3 rats.

Table 5 shows the pharmacokinetic parameters C_(max) (maximal observedconcentration), t_(1/2) (elimination half-life) AUC (area under thecurve), Vss (distribution volume at steady state), clearance rate, andMRT (mean residence time) for unmodified IFN-β-1a and these forms ofPEGylated IFN-β-1a. The data shown in FIGS. 8A and 8B and in Table 5were obtained in the same study.

FIG. 9A shows the concentration versus time plots for unmodifiedIFN-β-1a (upper panel) and IFN-β-1a modified with 20 kDamPEG-O-p-phenylpropionaldehyde (lower panel). Data points are averagesfrom measurements from 2 rats. FIG. 9B shows the concentration versustime plots for IFN-β-1a modified with 20 kDa mPEG-O-m-phenylacetaldehyde(upper panel) and 20 kDa mPEG-O-m-methylphenyl-O-2-methylpropionaldehyde(lower panel). Data points are averages from measurements from 3 rats.

Table 6 shows the pharmacokinetic parameters for unmodified IFN-β-1a andthese forms of PEGylated IFN-β-1a. The data shown in FIGS. 9A and 9B andin Table 6 were obtained in the same study; independent from the datashown in FIGS. 8A and 8B, and in Table 5.

As is clear from the data shown in FIGS. 8A, 8B, 9A, and 9B, and inTables 5 and 6, PEGylation of IFN-β-1a with the PEG molecules of theinvention improves the pharmacokinetic properties of IFN-β-1a. In allcases, the PEGylated proteins were cleared less rapidly than unmodifiedIFN-β-1a, resulting in clearance rates of 3.9-8.3 mL/h/kg as compared to160-170 mL/h/kg for the unmodified protein. As a consequence of thereduced clearance rates, the mean residence time (MRT) increased fromapproximately 1 h for the unmodified protein to 4.8-7.6 h for thePEGylated proteins. Similarly, the elimination half-life (t_(1/2))increased from approximately 1 h for the unmodified protein to 5.2-13 hfor the PEGylated proteins. The area under the curve (AUC) values werealso significantly increased upon PEGylation of IFN-β-1a. For unmodifiedIFN-β-1a, the AUC was approximately 0.5 μg·h/mL while for the PEGylatedproteins the AUC values ranged from approximately 3 to 6 μg·h/mL,despite the fact that the PEGylated proteins were dosed at a level3.3-fold lower than the unmodified protein. For the maximal observedconcentration (C_(max)), the values were generally higher for unmodifiedIFN-β-1a than for the PEGylated proteins, reflecting the lower dose ofthe modified proteins administered. For the volume of distribution atsteady state (Vss), the values for all the PEGylated proteins were lowerthan for unmodified IFN-β-1a, indicating a restriction in their abilityto exit the central blood compartment.

TABLE 5 Pharmacokinetic parameters for unmodified IFN-β-1a, 20 kDamPEG-O-2- methylpropionaldehyde-modified IFN-β-1a, 20 kDamPEG-O-p-methylphenyl-O-2- methylpropionaldehyde-modified IFN-β-1a, and20 kDa mPEG-O-p-phenylacetaldehyde- modified IFN-β-1a followingintravenous administration in rats^(a) 20 kDa mPEG-O-p- 20 kDa mPEG-O-2-methylphenyl-O-2- 20 kDa mPEG-O-p- Unmodified methylpropionaldehyde-methylpropionaldehyde- phenylacetaldehyde- Parameter Units IFN-β-1amodified IFN-β-1a modified IFN-β-1a modified IFN-β-1a C_(max) pg/mL1,400,000 720,000 710,000 590,000 t_(1/2) h 0.98 13 11 6.8 AUC pg · h/mL510,000 4,800,000 4,500,000 2,900,000 Vss mL/kg 160 39 40 53 ClearancemL/h/kg 160 5.0 5.3 8.3 MRT h 0.98 7.6 7.4 6.4 ^(a)The pharmacokineticdata for the unmodified and PEGylated IFNs-β-1a shown were obtained inthe same study

TABLE 6 Pharmacokinetic parameters for unmodified IFN-β-1a, 20 kDamPEG-O-p- phenylpropionaldehyde-modified IFN-β-1a, 20 kDamPEG-O-m-phenylacetaldehyde- modified IFN-β-1a, and 20 kDamPEG-O-m-methylphenyl-O-2-methylpropionaldehyde- modified IFN-β-1afollowing intravenous administration in rats^(a) 20 kDa mPEG-O-m- 20 kDamPEG-O-m- 20 kDa mPEG-O-p- phenylacetaldehyde- methylphenyl-O-2-Unmodified phenylpropionaldehyde- modified methylpropionaldehyde-Parameter Units IFN-β-1a modified IFN-β-1a IFN-β-1a modified IFN-β-1aC_(max) pg/mL 670,000 930,000 550,000 700,000 t_(1/2) h 0.92 5.2 7.7 7.1AUC pg · h/mL 470,000 4,700,000 3,800,000 6,200,000 Vss mL/kg 140 25 4621 Clearance mL/h/kg 170 5.1 6.4 3.9 MRT h 0.81 4.8 7.2 5.5 ^(a)Thepharmacokinetic data for the unmodified and PEGylated IFNs-β-1a shownwere obtained in the same study.

Example 5 Comparative Pharmacokinetics and Pharmacodynamics ofUnmodified and PEGylated Human IFN-β-1a in Non-human Primates

Single and repeat dose comparative studies are conducted with unmodifiedand PEGylated IFN-β-1a to determine their relative stability andactivity in non-human primates. In these studies, the pharmacokineticsand pharmacodynamics of the PEGylated conjugates is compared to that ofunmodified IFN-β-1a and reasonable inferences can be extended to humans.

Animals and Methods

Study 1 (repeat dose)

This is a parallel group, repeat dose study to evaluate the comparativepharmacokinetics and pharmacodynamics of unmodified and PEGylatedIFN-1′-1a. Healthy primates (e.g., rhesus monkeys) are used for thisstudy. Prior to dosing, all animals are evaluated for signs of illhealth by a laboratory animal veterinarian on two occasions within 14days prior to test article administration; one evaluation must be within24 h prior to the first test article administration. Only healthyanimals receive the test article. Evaluations include a general physicalexamination and pre-dose blood draws for baseline clinical pathology andbaseline antibody level to IFN-β-1a. All animals are weighed and bodytemperatures are recorded within 24 h prior to test articleadministrations. Twelve subjects are enrolled and assigned to groups ofthree to receive 1×10⁶ U/kg of unmodified or PEGylated IFN-β-1a, butotherwise identical IFN-β-1a. Administration is by either thesubcutaneous (SC) or intravenous (IV) routes. Six male animals receivetest article by the IV route (3 per treatment) and another 6 maleanimals receive test article by the SC route (3 per treatment). Allanimals must be naive to IFN-β treatment. Each animal is dosed on twooccasions, the doses are separated by four weeks. The dose volume is 1.0mL/kg. Blood is drawn for pharmacokinetic testing at 0, 0.083, 0.25,0.5, 1, 1.5, 2, 4, 6, 8, 12, 24, 48, 72, and at 96 hours following eachinjection. Blood samples for measurement of the IFN-induced biologicalresponse marker, serum neopterin, are drawn at 0, 24, 48, 72, 96, 168,336, and at 504 h following administration of study drug. Evaluationsduring the study period include clinical observations performed 30 minand 1 h post-dose for signs of toxicity. Daily cage-side observationsare performed and general appearance, signs of toxicity, discomfort, andchanges in behavior are recorded. Body weights and body temperatures arerecorded at regular intervals through 21 days post-dose.

Study 2 (Single Dose)

This is a parallel group, single dose study to evaluate the comparativepharmacokinetics and pharmacodynamics of unmodified and PEGylatedIFN-β-1a. Healthy primates (e.g., rhesus monkeys) are used for thisstudy. Prior to dosing, all animals are evaluated for signs of illhealth by a laboratory animal veterinarian on two occasions within 14days prior to test article administration; one evaluation must be within24 h prior to the first test article administration. Only healthyanimals receive the test article. Evaluations include a general physicalexamination and pre-dose blood draws for baseline clinical pathology andbaseline antibody level to IFN-β-1a. All animals are weighed and bodytemperatures are recorded within 24 h prior to test articleadministrations. Twenty subjects are enrolled and assigned to one offive groups of four animals (2 male and 2 female per group) to receiveeither 1×10⁶ U/kg of unmodified or PEGylated IFN-β-1a intramuscularly(IM), or 2×10⁵ U/kg, 1×10⁶ U/kg, or 5×10⁶ U/kg of PEGylated IFN-β-1aintravenously (IV). All animals must be naive to IFN-β treatment. Thedose volume is generally 1.0 mL/kg. Blood is drawn for pharmacokinetictesting at 0, 0.5, 1, 2, 4, 6, 8, 12, 24, 36, 48, and at 96 hours, andat 7, 14, 21, and at 28 days following administration of study drug.Blood samples for measurement of the IFN-induced biological responsemarker, 2′-5′-oligoadenylate synthase (2′-5′-OAS), are drawn at 0, 12,24, 48, 72, and at 96 hours, and at 7, 14, 21, and at 28 days followingadministration of study drug. Evaluations during the study periodinclude clinical observations performed 30 min and 1 h post-dose forsigns of toxicity. Daily cage-side observations are performed andgeneral appearance, signs of toxicity, discomfort, and changes inbehavior are recorded. Body weights and body temperatures are recordedat regular intervals through 28 days post-dose.

Assay Methods

Levels of IFN-β-1a in serum are quantitated using a cytopathic effect(CPE) bioassay.

The CPE assay measures levels of IFN-mediated antiviral activity. Thelevel of antiviral activity in a sample reflects the number of moleculesof active IFN contained in that sample at the time the blood is drawn.This approach has been the standard method to assess thepharmacokinetics of IFN-β. The CPE assay detects the ability of IFN-β toprotect human lung carcinoma cells (A549, #CCL-185, ATCC, Rockville,Md.) from cytotoxicity due to encephalomyocarditis (EMC) virus. Thecells are preincubated for 15-20 h with serum samples to allow theinduction and synthesis of IFN-inducible proteins that are responsiblefor the antiviral response. EMC virus is then added and incubated for afurther 30 h before assessment of cytotoxicity is made using a crystalviolet stain. An internal IFN-β standard as well as a PEGylated IFN-β-1ainternal standard is tested concurrently with samples on each assayplate. This standard is calibrated against a natural human fibroblastIFN reference standard (WHO Second International Standard forInterferon, Human Fibroblast, Gb-23-902-53). Each assay plate alsoincludes cell growth control wells containing neither IFN-β of any kindnor EMC, and virus control wells that contain cells and EMC but noIFN-β. Control plates containing the standard and samples are alsoprepared to determine the effect, if any, of the samples on cell growth.These plates are stained without the addition of virus. Samples andstandards are tested in duplicate on each of two replicate assay plates,yielding four data points per sample. The geometric mean concentrationof the four replicates is reported. The limit of detection in this assayis 10 U/mL. Serum concentrations of neopterin are determined at theclinical pharmacology unit using commercially-available assays. Serumconcentrations of 2′-5′-OAS are determined at a contract laboratoryusing a validated commercially-available assay.

Pharmacokinetic and Statistical Methods

Rstrip™ software (MicroMath, Inc., Salt Lake City, Utah) is used to fitdata to pharmacokinetic models. Geometric mean concentrations areplotted by time for each group. Since assay results are expressed indilutions, geometric means are considered more appropriate thanarithmetic means. Serum IFN levels are adjusted for baseline values andnon-detectable serum concentrations are set to 5 U/mL, which representsone-half the lower limit of detection. For IV infusion data, a twocompartment IV infusion model is fit to the detectable serumconcentrations for each subject, and the SC data are fit to a twocompartment injection model.

The following pharmacokinetic parameters are calculated:

(i) observed peak concentration, C_(max) (U/mL);

(ii) area under the curve from 0 to 48 h, AUC (U×h/mL) using thetrapezoidal rule;

(iii) elimination half-life (h); and, from IV infusion data (if IV isemployed):

(iv) distribution half-life (h);

(v) clearance (mL/h/kg)

(vi) apparent volume of distribution, Vd (mL/kg).

WinNonlin (Version 1.0, Scientific Consulting Inc., Apex, N.C.) softwareis used to calculate the elimination half-lives after IV and SCinjection. For neopterin and 2′-5′-OAS, arithmetic means by time arepresented for each group. E_(max), the maximum change from baseline, iscalculated. AUC, and E_(max) are submitted to a one-way analysis ofvariance to compare dosing groups. C_(max) and AUC arelogarithmically-transformed prior to analysis; geometric means arereported.

Example 6 Anti-Angiogenic Effects of PEGylated Human IFN-β-1a; theAbility of PEGylated IFN-β-1a to Inhibit Endothelial Cell ProliferationIn Vitro

Human venous endothelial cells (Cell Systems, Cat. # 2V0-P75) and humandermal microvascular endothelial cells (Cell Systems, Cat. # 2M1-C25)are maintained in culture with CS-C Medium Kit (Cell Systems, Cat. #4Z0-500). 24 h prior to the experiment, cells are trypsinized, andresuspended in assay medium, 90% M199 and 10% fetal bovine serum (FBS),and are adjusted to desired cell density. Cells are then plated ontogelatin-coated 24 or 96 well plates, either at 12,500 cells/well or2,000 cells/well, respectively. After overnight incubation, the assaymedium is replaced with fresh medium containing 20 ng/mL of humanrecombinant basic Fibroblast Growth Factor (bFGF) (Becton Dickinson,Cat. # 40060) and various concentrations of unmodified or PEGylatedIFN-β-1a of the invention or positive control (endostatin can be used asa positive control, as could an antibody to bFGF) are added. The finalvolume is adjusted to 0.5 mL in the 24 well plate or 0.2 mL in the 96well plate. After 72 h, cells are trypsinized for Coulter counting,frozen for CyQuant fluorescence reading, or labeled with [³H]-thymidine.This in vitro assay tests the PEGylated human IFN-β-1a molecules of theinvention for effects on endothelial cell proliferation which may beindicative of anti-angiogenic effects in vivo. See O'Reilly, et al.,Cell 88: 277-285 (1997).

Example 7 In vivo Models to Test Anti-angiogenic and NeovascularizationEffects of PEGylated Human IFN-β-1a and PEGylated Rodent IFNs-β

Unmodified IFN-β-1a and 20 kDa mPEG-O-2-methylpropionaldehyde-modifiedIFN-β-1a were tested for their ability to inhibit the formation ofradially-oriented vessels entering the periphery of SK-MEL-1 humanmalignant melanoma tumors in athymic nude homozygous (nu/nu) mice.SK-MEL-1 cells were grown in culture to 80% confluency, and then 2×10⁶cells inoculated intradermally (0.1 mL volume on day 0) into the flankin the mid-axillary line in three week old athymic nude homozygous(nu/nu) NCR mice (Taconic, Germantown, N.Y.). 24 hours later (day 1),groups of three mice each received the following subcutaneous doses ofvehicle control, unmodified IFN-β-1a, or 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a:

-   -   Group A: 0.1 mL of 45.6 mg/mL human serum albumin (vehicle        control) once on day 1 only    -   Group B: 0.1 mL of 45.6 mg/mL human serum albumin containing 1        MU (5 μg) of unmodified IFN-β-1a daily on days 1-9 inclusive    -   Group C: 0.1 mL of 45.6 mg/mL human serum albumin containing 1        MU units (10 μg) of 20 kDa        mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a once on day 1        only    -   Group D: 0.1 mL of 45.6 mg/mL human serum albumin (vehicle        control) daily on days 1-9 inclusive

Mice were sacrificed on day 10 (Avertin, 0.5 mL intraperitoneally) andthe tumor inoculation site assessed for neovascularization, measured byan observer blind as to treatment group. Vessels were counted underfixed magnification under a dissecting microscope. Everyradially-oriented vessel entering the periphery of the tumor was scoredas a single vessel. Each group consisted of three mice.

As shown in FIG. 10, a single administration of 1 MU of 20 kDamPEG-O-2-methylpropionaldehyde-modified IFN-β-1a (group C) was aseffective at reducing the number of neovessels as daily administrationof 1 MU of unmodified IFN-β-1a (group B). However, the effect of the 20kDa mPEG-O-2-methylpropionaldehyde-modified IFN-β-1a is more pronouncedwhen considering that daily administration of the vehicle alone had someinhibitory effect (compare group A, vehicle given once, with group D,vehicle given daily).

A variety of other models have also been developed which can be used totest the anti-angiogenic and anti-neovascularization effects of thePEGylated molecules of the invention. Some of these models have beendescribed in U.S. Pat. No. 5,733,876 (Mar. 31, 1998: “Method ofinhibiting angiogenesis”) and U.S. Pat. No. 5,135,919 (Aug. 4, 1992:“Method and a pharmaceutical composition for the inhibition ofangiogenesis”). Other assays include the shell-less chorioallantoicmembrane (CAM) assay of Taylor and Folkman; Nature 297:307 (1982) andCrum et al., Science 230:1375 (1985); the mouse dorsal air sac methodanti-angiogenesis model of Folkman et al.; J. Exp. Med. 133: 275 (1971),and the rat corneal micropocket assay of Gimbrone, Jr. et al., J. Natl.Cancer Inst. 52:413 (1974) in which corneal vascularization is inducedin adult male rats of the Sprague-Dawley strain (Charles River, Japan)by implanting 500 ng of bFGF (bovine, R & D Systems, Inc.), impregnatedin ethylene-vinyl acetate copolymer pellets, in each cornea. Inaddition, a model exists in which angiogenesis is induced in NIH-Swissor athymic nude (nu/nu) mice after implantation of MCF-7 breastcarcinoma or NIH-OVCAR-3 ovarian carcinoma cells as described by Lindnerand Borden; Int. J. Cancer 71:456 (1997). Additional tumor cell linesincluding (but not limited to) SK-MEL-1 human malignant melanoma cellsmay also be used to induce angiogenesis as described above. Variousdoses, with various dosing frequencies, and for various duration can betested for both the unmodified and PEGylated IFN-β-1a proteins of theinvention.

Other methods for testing PEGylated murine and rat IFN-β foranti-angiogenic effects in an animal model include (but are not limitedto) protocols for screening new potential anticancer agents as describedin the original Cancer Chemotherapy Reports, Part 3, Vol. 3, No. 2,September 1972 and the supplement In Vivo Cancer Models, 1976-1982, NIH

Publication No. 84-2635, February 1984. Because of the speciesspecificity of Type I interferons, to assess the anti-angiogenicactivity of PEGylated IFN-β in rodent models, PEGylated rodent IFN-βpreparations (e.g., murine and rat) are generated. Such screeningmethods are exemplified by a protocol to test for the anti-angiogeniceffects of PEGylated murine IFN-β on subcutaneously-implanted Lewis LungCarcinoma:

Origin of Tumor Line

This tumor line arose spontaneously in 1951 as a carcinoma of the lungin a C57BL/6 mouse.

Summary of Test Procedure

A tumor fragment is implanted subcutaneously in the axillary region of aB6D2F1 mouse. The test agent (i.e., a PEGylated interferon of theinvention) is administered at various doses, subcutaneously (SC) orintraperitoneally (IP) on multiple days following tumor implantation.The parameter measured is median survival time. Results are expressed asa percentage of control survival time.

Animals

-   -   Propagation: C57BL16 mice.    -   Testing: B6D2F1 mice.    -   Weight: Mice are within a 3 g weight range, with a minimum        weight of 18 g for males and 17 g for females.    -   Sex: One sex is used for all test and control animals in one        experiment.    -   Source: One source, if feasible, for all animals in one        experiment.

Experiment Size

-   -   Ten animals per test group.

Tumor Transfer

Propagation:

-   -   Fragment: Prepare a 2-4 mm fragment of a SC donor tumor.    -   Time: Day 13-15.    -   Site: Implant the fragment SC in the axillary region with a        puncture in the inguinal region.        Testing:    -   Fragment: Prepare a 2-4 mm fragment of SC donor tumor.    -   Time: Day 13-15.    -   Site: Implant the fragment SC in the axillary region with a        puncture in the inguinal region.

Testing Schedule

-   -   Day 0: Implant tumor. Run bacterial cultures. Test positive        control compound in every odd-numbered experiment. Prepare        materials. Record deaths daily.    -   Day 1: Check cultures. Discard experiment if contaminated.        Randomize animals. Treat as instructed (on day 1 and on        following days).    -   Day 2: Recheck cultures. Discard experiment if contaminated.    -   Day 5: Weigh Day 2 and day of initial test agent toxicity        evaluation.    -   Day 14: Control early-death day.    -   Day 48: Control no-take day.    -   Day 60: End and evaluate experiment. Examine lungs for tumor.

Quality Control

Schedule the positive control compound (NSC 26271; Cytoxan at a dose of100 mg/kg/injection) in every odd-numbered experiment, the regimen forwhich is intraperitoneal on Day 1 only. The lower Test/Control limit forthe positive control is 140%. The acceptable untreated control mediansurvival time is 19-35.6 days.

Evaluation

The parameter measured is median survival time. Compute the mean animalbody weights for Day 1 and Day 5, compute Test/Control ratio for alltest groups. The mean animal body weights for staging day and finalevaluation day are computed. The Test/Control ratio is computed for alltest groups with >65% survivors on Day 5. A Test/Control ratio value<86% indicates toxicity. An excessive body weight change difference(test minus control) may also be used in evaluating toxicity.

Criteria for Activity

An initial Test/Control ratio greater than or equal to 140% isconsidered necessary to demonstrate moderate activity. A reproducibleTest/Control ratio value of greater than or equal to 150% is consideredsignificant activity.

Example 8 In vivo Models to Test the Antiproliferative and Anti-TumorEffects of PEGylated Human IFN-β-1a and PEGylated Rodent IFNs-β

Various in vivo models are available to test the anti-proliferative andanti-tumor effects of unmodified and PEGylated human IFNs-β-1a of theinvention. In a model described by Bailon et al., Bioconjugate Chemistry12:195 (2001), athymic nude mice (Harlan) are implanted subcutaneouslywith 2×10⁶ human renal A498, human renal ACHN, or human renal G402 cellsunder the rear flank and 3-6 weeks allowed for tumors to develop.Unmodified or PEGylated human IFN-β-1a is then administered at variousdoses, with various dosing frequencies, and for various duration, andtumor volume measured and compared between treatments. In another modeldescribed by Lindner and Borden, J. Interferon Cytokine Res 17: 681(1997), athymic nude (nu/nu) oophorectomized female BALB/c mice areimplanted with 2×10⁶ MCF-7 (plus estradiol), MDA-MB-231, MDA-MB-468, orBT-20 human breast carcinoma cells, NIH-OVCAR-3 human ovarian carcinomacells, HT-29 human colon carcinoma cells, or SK-MEL-1 or FEMX humanmalignant melinoma cells, into the dermis overlying the mammary glandsnearest the axillae, and the size of the tumors assessed as a functionof time. Unmodified or PEGylated human IFN-β-1a is then administered atvarious doses, with various dosing frequencies, and for variousduration, and tumor volume measured and compared between treatments.Other models for testing the anti-proliferative and anti-tumor effectsof PEGylated human IFN-β-1a include (but are not limited to) local andmetastatic lung cancer models described by Qin et al., Molecular Therapy4: 356 (2001), and nude mouse xenograft models of human colorectalcancer liver metastases described by Tada et al, J ClinicalInvestigation 108: 83 (2001).

Other methods for testing PEGylated murine and rat IFN-β foranti-proliferative and anti-tumor effects in animal models include (butare not limited to) a mouse model of malignant mesothelioma described byOdaka et al., Cancer Res 61: 6201 (2001), local and metastatic lungcancer models described by Qin et al., Molecular Therapy 4: 356 (2001),and syngeneic mouse models of colorectal cancer liver metastasesdescribed by Tada et al., J Clinical Investigation 108: 83 (2001).

Example 9 In vivo Models to Test Anti-Viral Effects of PEGylated MurineIFN-β and PEGylated Human IFN-β-1a

An in vivo mouse model is available to test the effect of unmodified andPEGylated murine IFN-β on the levels of human Hepatitis B Virus (HBV) inHBV-transgenic SCID mice. Larkin et al., Nature Medicine 5:907 (1999).In this model, transgenic SCID mice carrying a head-to-tail dimer of thehuman HBV genome have detectable levels of HBV replicative forms andpre-genomic RNA in the liver, and HBV virus in the serum. Hepatocytesfrom the transgenic mice are also positive for the HBsAg, HBcAg, andHbxAg proteins, indicative of viral replication. An example of aprotocol for comparing unmodified and PEGylated murine IFN-β in thismodel is given below:

30 mice (5 groups of 5 plus 5 spare) with comparable viral titer aretitered at two independent time points (at least 1 week apart) toestablish a baseline titer and to ensure that their titers remainconstant prior to dosing with murine IFN-β. Groups of 5 mice are dosed 3times per week (Monday, Wednesday, and Friday) subcutaneously with thefollowing samples, as shown in Table 7.

TABLE 7 Group Dosing sample 1 Vehicle control (1 mg/mL murine serumalbumin, MSA) 2 30 U unmodified murine IFN-β in 1 mg/mL MSA 3 300 Uunmodified murine IFN-β in 1 mg/mL MSA 4 3000 U unmodified murine IFN-βin 1 mg/mL MSA 5 30 U PEGylated murine IFN-β in 1 mg/mL MSA 6 300 UPEGylated murine IFN-β in 1 mg/mL MSA 7 3000 U PEGylated murine IFN-β in1 mg/mL MSA

Viral titers are determined weekly during dosing and weekly to bi-weeklyfor 6 months following dosing. Plots of viral titer against time areconstructed for a comparison of vehicle and IFN-β-treated animals withrespect to the clearance and re-establishment of viral titer. A secondstudy is then performed with the appropriate doses of unmodified andPEGylated murine IFN-β with 10-20 mice per group for a total of 30-60mice (10-20 for control, 10-20 for unmodified murine IFN-β, and 10-20for PEGylated murine IFN-β). Viral titers are assessed as above, and atsacrifice, serum is analyzed for viral titer as well as for HbsAg bySDS-PAGE and Western blotting. Livers are also removed, frozen or fixedas necessary, and stained for the presence of HbsAg, HbcAg, and HbxAg.Other appropriate histological, histochemical, or biochemical testsfamiliar to those in the art may also be performed on serum and tissuesamples.

An in vivo mouse model is also available to test the effect ofunmodified and PEGylated human IFN-β-1a on the levels of human HepatitisC Virus (HCV) in mice carrying chimaeric human livers. Mercer et al.,Nature Medicine 7:927 (2001). In this model, normal human hepatocytesare grafted into SCID mice carrying a plasminogen activator transgene

(Alb-uPA) and the mice inoculated with serum from humans infected withthe different gentoypes of HCV. The engrafted human liver cells becomeinfected by the virus and the virus replicates. Levels of HCV RNA in theserum can be quantified by PCR, as well as the levels of positive andnegative (replicative form) RNA in the liver cells. An appropriate studyprotocol similar to (but not limited to) that described above forunmodified and PEGylated murine IFN-β in transgenic HBV SCID mice isperformed to assess the efficacy of unmodified and PEGylated humanIFN-β-1a in this model i.e. to determine the effect of treatment on HCVtiter, liver histology, serum ALT levels, and the presence of HCVreplicative forms in the engrafted human liver tissue. Other appropriatehistological, histochemical, or biochemical tests familiar to those inthe art may also be performed on serum and tissue samples.

We claim:
 1. A method of treating a patient having aninterferon-susceptible viral infection, comprising administering to thepatient an effective amount of a composition having the structureaccording to the formula

wherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; a is an integer from 4 to 10,000; each Zand Z′ is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein in the substitutedgroups the substitution is selected from the group consisting ofhalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, an aromatic moiety, a heteroaromatic moiety,imino, silyl, ether, and alkylthio, provided that at least one Z or Z′is not hydrogen; R* is a linking moiety formed from the reaction of amoiety selected from the group consisting of aldehyde, aldehyde hydrate,and acetal, with B, wherein B is a biologically-active molecule orprecursor thereof that comprises interferon-beta-1a (IFN-β-1a); each nis 0 or an integer from 1 to 5; and p is 1, 2, or
 3. 2. The method ofclaim 1, wherein the viral infection is chronic hepatitis C.
 3. A methodof treating multiple sclerosis in a patient suffering therefrom,comprising administering to said patient an effective amount of acomposition having the structure according to the formula

wherein E is hydrogen, a straight- or branched-chain C₁ to C₂₀ alkylgroup, or a detectable label; a is an integer from 4 to 10,000; each Zand Z′ is independently hydrogen, a straight- or branched-chain,saturated or unsaturated C₁ to C₂₀ alkyl or heteroalkyl group, C₃ to C₈saturated or unsaturated cyclic alkyl or cyclic heteroalkyl, asubstituted or unsubstituted aryl or heteroaryl group or a substitutedor unsubstituted alkaryl wherein the alkyl is a C₁ to C₂₀ saturated orunsaturated alkyl or heteroalkaryl group, wherein in the substitutedgroups the substitution is selected from the group consisting ofhalogen, hydroxyl, carbonyl, carboxylate, ester, formyl, acyl,thiocarbonyl, thioester, thioacetate, thioformate, alkoxyl, phosphoryl,phosphonate, phosphinate, amino, amido, amidine, imine, cyano, nitro,azido, sulfhydryl, sulfate, sulfonate, sulfamoyl, sulfonamido, sulfonyl,heterocyclyl, aralkyl, an aromatic moiety, a heteroaromatic moiety,imino, silyl, ether, and alkylthio, provided that at least one Z or Z′is not hydrogen; R* is a linking moiety formed from the reaction of amoiety selected from the group consisting of aldehyde, aldehyde hydrate,and acetal, with B, wherein B is a biologically-active molecule orprecursor thereof that comprises interferon-beta-1a (IFN-β-1a); each nis 0 or an integer from 1 to 5; and p is 1, 2, or 3.